diff --git a/.coveragerc b/.coveragerc
index 8583f9a5229..3c70bf1e4d8 100644
--- a/.coveragerc
+++ b/.coveragerc
@@ -1198,6 +1198,7 @@ omit =
     homeassistant/components/tuya/climate.py
     homeassistant/components/tuya/const.py
     homeassistant/components/tuya/cover.py
+    homeassistant/components/tuya/diagnostics.py
     homeassistant/components/tuya/fan.py
     homeassistant/components/tuya/humidifier.py
     homeassistant/components/tuya/light.py
diff --git a/homeassistant/components/tuya/const.py b/homeassistant/components/tuya/const.py
index d0d9a0c83a7..c8ee86b208c 100644
--- a/homeassistant/components/tuya/const.py
+++ b/homeassistant/components/tuya/const.py
@@ -121,6 +121,7 @@ class DPCode(StrEnum):
     ALARM_SWITCH = "alarm_switch"  # Alarm switch
     ALARM_TIME = "alarm_time"  # Alarm time
     ALARM_VOLUME = "alarm_volume"  # Alarm volume
+    ALARM_MESSAGE = "alarm_message"
     ANGLE_HORIZONTAL = "angle_horizontal"
     ANGLE_VERTICAL = "angle_vertical"
     ANION = "anion"  # Ionizer unit
@@ -224,6 +225,7 @@ class DPCode(StrEnum):
     MOTION_SENSITIVITY = "motion_sensitivity"
     MOTION_SWITCH = "motion_switch"  # Motion switch
     MOTION_TRACKING = "motion_tracking"
+    MOVEMENT_DETECT_PIC = "movement_detect_pic"
     MUFFLING = "muffling"  # Muffling
     NEAR_DETECTION = "near_detection"
     PAUSE = "pause"
diff --git a/homeassistant/components/tuya/diagnostics.py b/homeassistant/components/tuya/diagnostics.py
new file mode 100644
index 00000000000..238945c7eb5
--- /dev/null
+++ b/homeassistant/components/tuya/diagnostics.py
@@ -0,0 +1,156 @@
+"""Diagnostics support for Tuya."""
+from __future__ import annotations
+
+from contextlib import suppress
+import json
+from typing import Any, cast
+
+from tuya_iot import TuyaDevice
+
+from homeassistant.config_entries import ConfigEntry
+from homeassistant.core import HomeAssistant, callback
+from homeassistant.helpers import device_registry as dr, entity_registry as er
+from homeassistant.util import dt as dt_util
+
+from . import HomeAssistantTuyaData
+from .const import (
+    CONF_APP_TYPE,
+    CONF_AUTH_TYPE,
+    CONF_COUNTRY_CODE,
+    CONF_ENDPOINT,
+    DOMAIN,
+    DPCode,
+)
+
+
+async def async_get_config_entry_diagnostics(
+    hass: HomeAssistant, entry: ConfigEntry
+) -> dict[str, Any]:
+    """Return diagnostics for a config entry."""
+    hass_data: HomeAssistantTuyaData = hass.data[DOMAIN][entry.entry_id]
+
+    mqtt_connected = None
+    if hass_data.home_manager.mq.client:
+        mqtt_connected = hass_data.home_manager.mq.client.is_connected()
+
+    return {
+        "endpoint": entry.data[CONF_ENDPOINT],
+        "auth_type": entry.data[CONF_AUTH_TYPE],
+        "country_code": entry.data[CONF_COUNTRY_CODE],
+        "app_type": entry.data[CONF_APP_TYPE],
+        "mqtt_connected": mqtt_connected,
+        "disabled_by": entry.disabled_by,
+        "disabled_polling": entry.pref_disable_polling,
+        "devices": [
+            _async_device_as_dict(hass, device)
+            for device in hass_data.device_manager.device_map.values()
+        ],
+    }
+
+
+@callback
+def _async_device_as_dict(hass: HomeAssistant, device: TuyaDevice) -> dict[str, Any]:
+    """Represent a Tuya device as a dictionary."""
+
+    # Base device information, without sensitive information.
+    data = {
+        "name": device.model,
+        "model": device.model,
+        "category": device.category,
+        "product_id": device.product_id,
+        "product_name": device.product_name,
+        "online": device.online,
+        "sub": device.sub,
+        "time_zone": device.time_zone,
+        "active_time": dt_util.utc_from_timestamp(device.active_time).isoformat(),
+        "create_time": dt_util.utc_from_timestamp(device.create_time).isoformat(),
+        "update_time": dt_util.utc_from_timestamp(device.update_time).isoformat(),
+        "function": {},
+        "status_range": {},
+        "status": {},
+        "home_assistant": {},
+    }
+
+    # Gather Tuya states
+    for dpcode, value in device.status.items():
+        # These statuses may contain sensitive information, redact these..
+        if dpcode in {DPCode.ALARM_MESSAGE, DPCode.MOVEMENT_DETECT_PIC}:
+            data["status"][dpcode] = "**REDACTED**"
+            continue
+
+        with suppress(ValueError, TypeError):
+            value = json.loads(value)
+        data["status"][dpcode] = value
+
+    # Gather Tuya functions
+    for function in device.function.values():
+        value = function.values
+        with suppress(ValueError, TypeError, AttributeError):
+            value = json.loads(cast(str, function.values))
+
+        data["function"][function.code] = {
+            "type": function.type,
+            "value": value,
+        }
+
+    # Gather Tuya status ranges
+    for status_range in device.status_range.values():
+        value = status_range.values
+        with suppress(ValueError, TypeError, AttributeError):
+            value = json.loads(status_range.values)
+
+        data["status_range"][status_range.code] = {
+            "type": status_range.type,
+            "value": value,
+        }
+
+    # Gather information how this Tuya device is represented in Home Assistant
+    device_registry = dr.async_get(hass)
+    entity_registry = er.async_get(hass)
+    hass_device = device_registry.async_get_device(identifiers={(DOMAIN, device.id)})
+    if hass_device:
+        data["home_assistant"] = {
+            "name": hass_device.name,
+            "name_by_user": hass_device.name_by_user,
+            "disabled": hass_device.disabled,
+            "disabled_by": hass_device.disabled_by,
+            "entities": [],
+        }
+
+        hass_entities = er.async_entries_for_device(
+            entity_registry,
+            device_id=hass_device.id,
+            include_disabled_entities=True,
+        )
+
+        for entity_entry in hass_entities:
+            state = hass.states.get(entity_entry.entity_id)
+            state_dict = None
+            if state:
+                state_dict = state.as_dict()
+
+                # Redact the `entity_picture` attribute as it contains a token.
+                if "entity_picture" in state_dict["attributes"]:
+                    state_dict["attributes"] = {
+                        **state_dict["attributes"],
+                        "entity_picture": "**REDACTED**",
+                    }
+
+                # The context doesn't provide useful information in this case.
+                state_dict.pop("context", None)
+
+            data["home_assistant"]["entities"].append(
+                {
+                    "disabled": entity_entry.disabled,
+                    "disabled_by": entity_entry.disabled_by,
+                    "entity_category": entity_entry.entity_category,
+                    "device_class": entity_entry.device_class,
+                    "original_device_class": entity_entry.original_device_class,
+                    "icon": entity_entry.icon,
+                    "original_icon": entity_entry.original_icon,
+                    "unit_of_measurement": entity_entry.unit_of_measurement,
+                    "state": state_dict,
+                }
+            )
+
+    return data