diff --git a/homeassistant/components/webmin/diagnostics.py b/homeassistant/components/webmin/diagnostics.py
new file mode 100644
index 00000000000000..86e2c9eef62eb8
--- /dev/null
+++ b/homeassistant/components/webmin/diagnostics.py
@@ -0,0 +1,35 @@
+"""Diagnostics support for Webmin."""
+from typing import Any
+
+from homeassistant.components.diagnostics import async_redact_data
+from homeassistant.config_entries import ConfigEntry
+from homeassistant.const import CONF_HOST, CONF_PASSWORD, CONF_UNIQUE_ID, CONF_USERNAME
+from homeassistant.core import HomeAssistant
+
+from .const import DOMAIN
+from .coordinator import WebminUpdateCoordinator
+
+TO_REDACT = {
+    CONF_HOST,
+    CONF_UNIQUE_ID,
+    CONF_USERNAME,
+    CONF_PASSWORD,
+    "address",
+    "address6",
+    "ether",
+    "broadcast",
+    "device",
+    "dir",
+    "title",
+    "entry_id",
+}
+
+
+async def async_get_config_entry_diagnostics(
+    hass: HomeAssistant, entry: ConfigEntry
+) -> dict[str, Any]:
+    """Return diagnostics for a config entry."""
+    coordinator: WebminUpdateCoordinator = hass.data[DOMAIN][entry.entry_id]
+    return async_redact_data(
+        {"entry": entry.as_dict(), "data": coordinator.data}, TO_REDACT
+    )
diff --git a/tests/components/webmin/snapshots/test_diagnostics.ambr b/tests/components/webmin/snapshots/test_diagnostics.ambr
new file mode 100644
index 00000000000000..f227f6332fe252
--- /dev/null
+++ b/tests/components/webmin/snapshots/test_diagnostics.ambr
@@ -0,0 +1,138 @@
+# serializer version: 1
+# name: test_diagnostics
+  dict({
+    'data': dict({
+      'active_interfaces': list([
+        dict({
+          'address': '**REDACTED**',
+          'address6': '**REDACTED**',
+          'broadcast': '**REDACTED**',
+          'edit': 1,
+          'fullname': 'lo',
+          'index': 0,
+          'mtu': 65536,
+          'name': 'lo',
+          'netmask': '255.0.0.0',
+          'netmask6': list([
+            128,
+          ]),
+          'scope6': list([
+            'host',
+          ]),
+          'up': 1,
+        }),
+        dict({
+          'address6': '**REDACTED**',
+          'edit': 1,
+          'ether': '**REDACTED**',
+          'fullname': 'enp6s0',
+          'index': 1,
+          'mtu': 1500,
+          'name': 'enp6s0',
+          'netmask6': list([
+          ]),
+          'scope6': list([
+          ]),
+          'up': 1,
+        }),
+        dict({
+          'address': '**REDACTED**',
+          'address6': '**REDACTED**',
+          'broadcast': '**REDACTED**',
+          'edit': 1,
+          'ether': '**REDACTED**',
+          'fullname': 'eno1',
+          'index': 2,
+          'mtu': 1500,
+          'name': 'eno1',
+          'netmask': '255.255.255.0',
+          'netmask6': list([
+            64,
+          ]),
+          'scope6': list([
+            'link',
+          ]),
+          'up': 1,
+        }),
+      ]),
+      'free_space': 8641328926720,
+      'fs': list([
+        dict({
+          'device': '**REDACTED**',
+          'dir': '**REDACTED**',
+          'free': 174511820800,
+          'ifree': 15091734,
+          'itotal': 15482880,
+          'iused': 391146,
+          'iused_percent': 3,
+          'total': 248431161344,
+          'type': 'ext4',
+          'used': 61225123840,
+          'used_percent': 26,
+        }),
+        dict({
+          'device': '**REDACTED**',
+          'dir': '**REDACTED**',
+          'free': 1044483624960,
+          'ifree': 183131475,
+          'itotal': 183140352,
+          'iused': 8877,
+          'iused_percent': 1,
+          'total': 5952635744256,
+          'type': 'ext4',
+          'used': 4608079593472,
+          'used_percent': 82,
+        }),
+        dict({
+          'device': '**REDACTED**',
+          'dir': '**REDACTED**',
+          'free': 7422333480960,
+          'ifree': 362787383,
+          'itotal': 366198784,
+          'iused': 3411401,
+          'iused_percent': 1,
+          'total': 11903838912512,
+          'type': 'ext4',
+          'used': 3881508986880,
+          'used_percent': 35,
+        }),
+      ]),
+      'load_15m': 1.0,
+      'load_1m': 0.98,
+      'load_5m': 1.02,
+      'mem_free': 26162544,
+      'mem_total': 32767008,
+      'swap_free': 1953088,
+      'swap_total': 1953088,
+      'total_space': 18104905818112,
+      'uptime': dict({
+        'days': 3,
+        'minutes': 23,
+        'seconds': 12,
+      }),
+      'used_space': 8550813704192,
+    }),
+    'entry': dict({
+      'data': dict({
+      }),
+      'disabled_by': None,
+      'domain': 'webmin',
+      'entry_id': '**REDACTED**',
+      'minor_version': 1,
+      'options': dict({
+        'host': '**REDACTED**',
+        'password': '**REDACTED**',
+        'port': 10000,
+        'ssl': True,
+        'username': '**REDACTED**',
+        'verify_ssl': False,
+      }),
+      'pref_disable_new_entities': False,
+      'pref_disable_polling': False,
+      'source': 'user',
+      'title': '**REDACTED**',
+      'unique_id': None,
+      'version': 1,
+    }),
+  })
+# ---
diff --git a/tests/components/webmin/test_diagnostics.py b/tests/components/webmin/test_diagnostics.py
new file mode 100644
index 00000000000000..33a349878d1b83
--- /dev/null
+++ b/tests/components/webmin/test_diagnostics.py
@@ -0,0 +1,23 @@
+"""Tests for the diagnostics data provided by the Webmin integration."""
+from syrupy.assertion import SnapshotAssertion
+
+from homeassistant.core import HomeAssistant
+
+from .conftest import async_init_integration
+
+from tests.components.diagnostics import get_diagnostics_for_config_entry
+from tests.typing import ClientSessionGenerator
+
+
+async def test_diagnostics(
+    hass: HomeAssistant,
+    hass_client: ClientSessionGenerator,
+    snapshot: SnapshotAssertion,
+) -> None:
+    """Test diagnostics."""
+    assert (
+        await get_diagnostics_for_config_entry(
+            hass, hass_client, await async_init_integration(hass)
+        )
+        == snapshot
+    )