diff --git a/homeassistant/components/systemmonitor/config_flow.py b/homeassistant/components/systemmonitor/config_flow.py
index 924f63c8d1c..0ff882d89da 100644
--- a/homeassistant/components/systemmonitor/config_flow.py
+++ b/homeassistant/components/systemmonitor/config_flow.py
@@ -8,11 +8,9 @@ from typing import Any
 import voluptuous as vol
 
 from homeassistant.components.binary_sensor import DOMAIN as BINARY_SENSOR_DOMAIN
-from homeassistant.components.homeassistant import DOMAIN as HOMEASSISTANT_DOMAIN
 from homeassistant.config_entries import ConfigFlowResult
 from homeassistant.core import callback
 from homeassistant.helpers import entity_registry as er
-from homeassistant.helpers.issue_registry import IssueSeverity, async_create_issue
 from homeassistant.helpers.schema_config_entry_flow import (
     SchemaCommonFlowHandler,
     SchemaConfigFlowHandler,
@@ -53,37 +51,6 @@ async def validate_sensor_setup(
     return {}
 
 
-async def validate_import_sensor_setup(
-    handler: SchemaCommonFlowHandler, user_input: dict[str, Any]
-) -> dict[str, Any]:
-    """Validate sensor input."""
-    # Standard behavior is to merge the result with the options.
-    # In this case, we want to add a sub-item so we update the options directly.
-    sensors: dict[str, list] = handler.options.setdefault(BINARY_SENSOR_DOMAIN, {})
-    import_processes: list[str] = user_input["processes"]
-    processes = sensors.setdefault(CONF_PROCESS, [])
-    processes.extend(import_processes)
-    legacy_resources: list[str] = handler.options.setdefault("resources", [])
-    legacy_resources.extend(user_input["legacy_resources"])
-
-    async_create_issue(
-        handler.parent_handler.hass,
-        HOMEASSISTANT_DOMAIN,
-        f"deprecated_yaml_{DOMAIN}",
-        breaks_in_ha_version="2024.7.0",
-        is_fixable=False,
-        is_persistent=False,
-        issue_domain=DOMAIN,
-        severity=IssueSeverity.WARNING,
-        translation_key="deprecated_yaml",
-        translation_placeholders={
-            "domain": DOMAIN,
-            "integration_title": "System Monitor",
-        },
-    )
-    return {}
-
-
 async def get_sensor_setup_schema(handler: SchemaCommonFlowHandler) -> vol.Schema:
     """Return process sensor setup schema."""
     hass = handler.parent_handler.hass
@@ -112,10 +79,6 @@ async def get_suggested_value(handler: SchemaCommonFlowHandler) -> dict[str, Any
 
 CONFIG_FLOW = {
     "user": SchemaFlowFormStep(schema=vol.Schema({})),
-    "import": SchemaFlowFormStep(
-        schema=vol.Schema({}),
-        validate_user_input=validate_import_sensor_setup,
-    ),
 }
 OPTIONS_FLOW = {
     "init": SchemaFlowFormStep(
diff --git a/homeassistant/components/systemmonitor/sensor.py b/homeassistant/components/systemmonitor/sensor.py
index 3634820ba30..bad4c3be0b5 100644
--- a/homeassistant/components/systemmonitor/sensor.py
+++ b/homeassistant/components/systemmonitor/sensor.py
@@ -15,20 +15,15 @@ import time
 from typing import Any, Literal
 
 from psutil import NoSuchProcess
-import voluptuous as vol
 
 from homeassistant.components.sensor import (
     DOMAIN as SENSOR_DOMAIN,
-    PLATFORM_SCHEMA,
     SensorDeviceClass,
     SensorEntity,
     SensorEntityDescription,
     SensorStateClass,
 )
-from homeassistant.config_entries import SOURCE_IMPORT
 from homeassistant.const import (
-    CONF_RESOURCES,
-    CONF_TYPE,
     PERCENTAGE,
     STATE_OFF,
     STATE_ON,
@@ -39,11 +34,10 @@ from homeassistant.const import (
 )
 from homeassistant.core import HomeAssistant, callback
 from homeassistant.helpers import entity_registry as er
-import homeassistant.helpers.config_validation as cv
 from homeassistant.helpers.device_registry import DeviceEntryType, DeviceInfo
 from homeassistant.helpers.entity_platform import AddEntitiesCallback
 from homeassistant.helpers.issue_registry import IssueSeverity, async_create_issue
-from homeassistant.helpers.typing import ConfigType, DiscoveryInfoType, StateType
+from homeassistant.helpers.typing import StateType
 from homeassistant.helpers.update_coordinator import CoordinatorEntity
 from homeassistant.util import slugify
 
@@ -410,20 +404,6 @@ SENSOR_TYPES: dict[str, SysMonitorSensorEntityDescription] = {
 }
 
 
-def check_required_arg(value: Any) -> Any:
-    """Validate that the required "arg" for the sensor types that need it are set."""
-    for sensor in value:
-        sensor_type = sensor[CONF_TYPE]
-        sensor_arg = sensor.get(CONF_ARG)
-
-        if sensor_arg is None and SENSOR_TYPES[sensor_type].mandatory_arg:
-            raise vol.RequiredFieldInvalid(
-                f"Mandatory 'arg' is missing for sensor type '{sensor_type}'."
-            )
-
-    return value
-
-
 def check_legacy_resource(resource: str, resources: set[str]) -> bool:
     """Return True if legacy resource was configured."""
     # This function to check legacy resources can be removed
@@ -435,23 +415,6 @@ def check_legacy_resource(resource: str, resources: set[str]) -> bool:
     return False
 
 
-PLATFORM_SCHEMA = PLATFORM_SCHEMA.extend(
-    {
-        vol.Optional(CONF_RESOURCES, default={CONF_TYPE: "disk_use"}): vol.All(
-            cv.ensure_list,
-            [
-                vol.Schema(
-                    {
-                        vol.Required(CONF_TYPE): vol.In(SENSOR_TYPES),
-                        vol.Optional(CONF_ARG): cv.string,
-                    }
-                )
-            ],
-            check_required_arg,
-        )
-    }
-)
-
 IO_COUNTER = {
     "network_out": 0,
     "network_in": 1,
@@ -463,44 +426,6 @@ IO_COUNTER = {
 IF_ADDRS_FAMILY = {"ipv4_address": socket.AF_INET, "ipv6_address": socket.AF_INET6}
 
 
-async def async_setup_platform(
-    hass: HomeAssistant,
-    config: ConfigType,
-    async_add_entities: AddEntitiesCallback,
-    discovery_info: DiscoveryInfoType | None = None,
-) -> None:
-    """Set up the system monitor sensors."""
-    processes = [
-        resource[CONF_ARG]
-        for resource in config[CONF_RESOURCES]
-        if resource[CONF_TYPE] == "process"
-    ]
-    legacy_config: list[dict[str, str]] = config[CONF_RESOURCES]
-    resources = []
-    for resource_conf in legacy_config:
-        if (_type := resource_conf[CONF_TYPE]).startswith("disk_"):
-            if (arg := resource_conf.get(CONF_ARG)) is None:
-                resources.append(f"{_type}_/")
-                continue
-            resources.append(f"{_type}_{arg}")
-            continue
-        resources.append(f"{_type}_{resource_conf.get(CONF_ARG, '')}")
-    _LOGGER.debug(
-        "Importing config with processes: %s, resources: %s", processes, resources
-    )
-
-    # With removal of the import also cleanup legacy_resources logic in setup_entry
-    # Also cleanup entry.options["resources"] which is only imported for legacy reasons
-
-    hass.async_create_task(
-        hass.config_entries.flow.async_init(
-            DOMAIN,
-            context={"source": SOURCE_IMPORT},
-            data={"processes": processes, "legacy_resources": resources},
-        )
-    )
-
-
 async def async_setup_entry(
     hass: HomeAssistant,
     entry: SystemMonitorConfigEntry,
diff --git a/tests/components/systemmonitor/test_config_flow.py b/tests/components/systemmonitor/test_config_flow.py
index bd98099accc..f5cc46da096 100644
--- a/tests/components/systemmonitor/test_config_flow.py
+++ b/tests/components/systemmonitor/test_config_flow.py
@@ -5,15 +5,10 @@ from __future__ import annotations
 from unittest.mock import AsyncMock
 
 from homeassistant import config_entries
-from homeassistant.components.homeassistant import DOMAIN as HOMEASSISTANT_DOMAIN
 from homeassistant.components.systemmonitor.const import CONF_PROCESS, DOMAIN
 from homeassistant.core import HomeAssistant
 from homeassistant.data_entry_flow import FlowResultType
-from homeassistant.helpers import (
-    device_registry as dr,
-    entity_registry as er,
-    issue_registry as ir,
-)
+from homeassistant.helpers import device_registry as dr, entity_registry as er
 
 from tests.common import MockConfigEntry
 
@@ -39,51 +34,6 @@ async def test_form(hass: HomeAssistant, mock_setup_entry: AsyncMock) -> None:
     assert len(mock_setup_entry.mock_calls) == 1
 
 
-async def test_import(
-    hass: HomeAssistant, mock_setup_entry: AsyncMock, issue_registry: ir.IssueRegistry
-) -> None:
-    """Test import."""
-
-    result = await hass.config_entries.flow.async_init(
-        DOMAIN,
-        context={"source": config_entries.SOURCE_IMPORT},
-        data={
-            "processes": ["systemd", "octave-cli"],
-            "legacy_resources": [
-                "disk_use_percent_/",
-                "memory_free_",
-                "network_out_eth0",
-                "process_systemd",
-                "process_octave-cli",
-            ],
-        },
-    )
-    await hass.async_block_till_done()
-
-    assert result["type"] is FlowResultType.CREATE_ENTRY
-    assert result["options"] == {
-        "binary_sensor": {"process": ["systemd", "octave-cli"]},
-        "resources": [
-            "disk_use_percent_/",
-            "memory_free_",
-            "network_out_eth0",
-            "process_systemd",
-            "process_octave-cli",
-        ],
-    }
-
-    assert len(mock_setup_entry.mock_calls) == 1
-
-    issue = issue_registry.async_get_issue(
-        HOMEASSISTANT_DOMAIN, f"deprecated_yaml_{DOMAIN}"
-    )
-    assert issue.issue_domain == DOMAIN
-    assert issue.translation_placeholders == {
-        "domain": DOMAIN,
-        "integration_title": "System Monitor",
-    }
-
-
 async def test_form_already_configured(
     hass: HomeAssistant, mock_setup_entry: AsyncMock
 ) -> None:
@@ -111,55 +61,6 @@ async def test_form_already_configured(
     assert result["reason"] == "already_configured"
 
 
-async def test_import_already_configured(
-    hass: HomeAssistant, mock_setup_entry: AsyncMock, issue_registry: ir.IssueRegistry
-) -> None:
-    """Test abort when already configured for import."""
-    config_entry = MockConfigEntry(
-        domain=DOMAIN,
-        source=config_entries.SOURCE_USER,
-        options={
-            "binary_sensor": [{CONF_PROCESS: "systemd"}],
-            "resources": [
-                "disk_use_percent_/",
-                "memory_free_",
-                "network_out_eth0",
-                "process_systemd",
-                "process_octave-cli",
-            ],
-        },
-    )
-    config_entry.add_to_hass(hass)
-
-    result = await hass.config_entries.flow.async_init(
-        DOMAIN,
-        context={"source": config_entries.SOURCE_IMPORT},
-        data={
-            "processes": ["systemd", "octave-cli"],
-            "legacy_resources": [
-                "disk_use_percent_/",
-                "memory_free_",
-                "network_out_eth0",
-                "process_systemd",
-                "process_octave-cli",
-            ],
-        },
-    )
-    await hass.async_block_till_done()
-
-    assert result["type"] is FlowResultType.ABORT
-    assert result["reason"] == "already_configured"
-
-    issue = issue_registry.async_get_issue(
-        HOMEASSISTANT_DOMAIN, f"deprecated_yaml_{DOMAIN}"
-    )
-    assert issue.issue_domain == DOMAIN
-    assert issue.translation_placeholders == {
-        "domain": DOMAIN,
-        "integration_title": "System Monitor",
-    }
-
-
 async def test_add_and_remove_processes(
     hass: HomeAssistant,
     device_registry: dr.DeviceRegistry,
diff --git a/tests/components/systemmonitor/test_sensor.py b/tests/components/systemmonitor/test_sensor.py
index 8f0f316b5f8..ce15083da67 100644
--- a/tests/components/systemmonitor/test_sensor.py
+++ b/tests/components/systemmonitor/test_sensor.py
@@ -17,7 +17,6 @@ from homeassistant.config_entries import ConfigEntry
 from homeassistant.const import STATE_OFF, STATE_ON, STATE_UNAVAILABLE, STATE_UNKNOWN
 from homeassistant.core import HomeAssistant
 from homeassistant.helpers import entity_registry as er
-from homeassistant.setup import async_setup_component
 
 from .conftest import MockProcess
 
@@ -142,58 +141,6 @@ async def test_sensor_icon(
         assert get_cpu_icon() == "mdi:cpu-64-bit"
 
 
-@pytest.mark.usefixtures("entity_registry_enabled_by_default")
-async def test_sensor_yaml(
-    hass: HomeAssistant,
-    mock_psutil: Mock,
-    mock_os: Mock,
-) -> None:
-    """Test the sensor imported from YAML."""
-    config = {
-        "sensor": {
-            "platform": "systemmonitor",
-            "resources": [
-                {"type": "disk_use_percent"},
-                {"type": "disk_use_percent", "arg": "/media/share"},
-                {"type": "memory_free", "arg": "/"},
-                {"type": "network_out", "arg": "eth0"},
-                {"type": "process", "arg": "python3"},
-            ],
-        }
-    }
-    assert await async_setup_component(hass, "sensor", config)
-    await hass.async_block_till_done()
-    memory_sensor = hass.states.get("sensor.system_monitor_memory_free")
-    assert memory_sensor is not None
-    assert memory_sensor.state == "40.0"
-
-    process_sensor = hass.states.get("binary_sensor.system_monitor_process_python3")
-    assert process_sensor is not None
-    assert process_sensor.state == STATE_ON
-
-
-@pytest.mark.usefixtures("entity_registry_enabled_by_default")
-async def test_sensor_yaml_fails_missing_argument(
-    caplog: pytest.LogCaptureFixture,
-    hass: HomeAssistant,
-    mock_psutil: Mock,
-    mock_os: Mock,
-) -> None:
-    """Test the sensor imported from YAML fails on missing mandatory argument."""
-    config = {
-        "sensor": {
-            "platform": "systemmonitor",
-            "resources": [
-                {"type": "network_in"},
-            ],
-        }
-    }
-    assert await async_setup_component(hass, "sensor", config)
-    await hass.async_block_till_done()
-
-    assert "Mandatory 'arg' is missing for sensor type 'network_in'" in caplog.text
-
-
 async def test_sensor_updating(
     hass: HomeAssistant,
     mock_psutil: Mock,