diff --git a/homeassistant/components/opentherm_gw/__init__.py b/homeassistant/components/opentherm_gw/__init__.py
index 8d1d3ae4d62..cc08ec3da69 100644
--- a/homeassistant/components/opentherm_gw/__init__.py
+++ b/homeassistant/components/opentherm_gw/__init__.py
@@ -26,6 +26,9 @@ from homeassistant.const import (
     PRECISION_WHOLE,
 )
 import homeassistant.helpers.config_validation as cv
+from homeassistant.helpers.device_registry import (
+    async_get_registry as async_get_dev_reg,
+)
 from homeassistant.helpers.dispatcher import async_dispatcher_send
 
 from .const import (
@@ -404,6 +407,7 @@ class OpenThermGatewayDevice:
         self.gw_id = config_entry.data[CONF_ID]
         self.name = config_entry.data[CONF_NAME]
         self.climate_config = config_entry.options
+        self.config_entry_id = config_entry.entry_id
         self.status = {}
         self.update_signal = f"{DATA_OPENTHERM_GW}_{self.gw_id}_update"
         self.options_update_signal = f"{DATA_OPENTHERM_GW}_{self.gw_id}_options_update"
@@ -419,9 +423,22 @@ class OpenThermGatewayDevice:
     async def connect_and_subscribe(self):
         """Connect to serial device and subscribe report handler."""
         self.status = await self.gateway.connect(self.hass.loop, self.device_path)
-        _LOGGER.debug("Connected to OpenTherm Gateway at %s", self.device_path)
-        self.gw_version = self.status.get(gw_vars.OTGW_BUILD)
-
+        version_string = self.status[gw_vars.OTGW].get(gw_vars.OTGW_ABOUT)
+        self.gw_version = version_string[18:] if version_string else None
+        _LOGGER.debug(
+            "Connected to OpenTherm Gateway %s at %s", self.gw_version, self.device_path
+        )
+        dev_reg = await async_get_dev_reg(self.hass)
+        gw_dev = dev_reg.async_get_or_create(
+            config_entry_id=self.config_entry_id,
+            identifiers={(DOMAIN, self.gw_id)},
+            name=self.name,
+            manufacturer="Schelte Bron",
+            model="OpenTherm Gateway",
+            sw_version=self.gw_version,
+        )
+        if gw_dev.sw_version != self.gw_version:
+            dev_reg.async_update_device(gw_dev.id, sw_version=self.gw_version)
         self.hass.bus.async_listen(EVENT_HOMEASSISTANT_STOP, self.cleanup)
 
         async def handle_report(status):
diff --git a/tests/components/opentherm_gw/test_init.py b/tests/components/opentherm_gw/test_init.py
new file mode 100644
index 00000000000..51d75bf0923
--- /dev/null
+++ b/tests/components/opentherm_gw/test_init.py
@@ -0,0 +1,73 @@
+"""Test Opentherm Gateway init."""
+from unittest.mock import patch
+
+from pyotgw.vars import OTGW, OTGW_ABOUT
+
+from homeassistant import setup
+from homeassistant.components.opentherm_gw.const import DOMAIN
+from homeassistant.const import CONF_DEVICE, CONF_ID, CONF_NAME
+
+from tests.common import MockConfigEntry, mock_device_registry
+
+VERSION_OLD = "4.2.5"
+VERSION_NEW = "4.2.8.1"
+MINIMAL_STATUS = {OTGW: {OTGW_ABOUT: f"OpenTherm Gateway {VERSION_OLD}"}}
+MINIMAL_STATUS_UPD = {OTGW: {OTGW_ABOUT: f"OpenTherm Gateway {VERSION_NEW}"}}
+MOCK_GATEWAY_ID = "mock_gateway"
+MOCK_CONFIG_ENTRY = MockConfigEntry(
+    domain=DOMAIN,
+    title="Mock Gateway",
+    data={
+        CONF_NAME: "Mock Gateway",
+        CONF_DEVICE: "/dev/null",
+        CONF_ID: MOCK_GATEWAY_ID,
+    },
+    options={},
+)
+
+
+async def test_device_registry_insert(hass):
+    """Test that the device registry is initialized correctly."""
+    MOCK_CONFIG_ENTRY.add_to_hass(hass)
+
+    with patch(
+        "homeassistant.components.opentherm_gw.OpenThermGatewayDevice.cleanup",
+        return_value=None,
+    ), patch("pyotgw.pyotgw.connect", return_value=MINIMAL_STATUS):
+        await setup.async_setup_component(hass, DOMAIN, {})
+
+    await hass.async_block_till_done()
+
+    device_registry = await hass.helpers.device_registry.async_get_registry()
+
+    gw_dev = device_registry.async_get_device(
+        identifiers={(DOMAIN, MOCK_GATEWAY_ID)}, connections=set()
+    )
+    assert gw_dev.sw_version == VERSION_OLD
+
+
+async def test_device_registry_update(hass):
+    """Test that the device registry is updated correctly."""
+    MOCK_CONFIG_ENTRY.add_to_hass(hass)
+
+    dev_reg = mock_device_registry(hass)
+    dev_reg.async_get_or_create(
+        config_entry_id=MOCK_CONFIG_ENTRY.entry_id,
+        identifiers={(DOMAIN, MOCK_GATEWAY_ID)},
+        name="Mock Gateway",
+        manufacturer="Schelte Bron",
+        model="OpenTherm Gateway",
+        sw_version=VERSION_OLD,
+    )
+
+    with patch(
+        "homeassistant.components.opentherm_gw.OpenThermGatewayDevice.cleanup",
+        return_value=None,
+    ), patch("pyotgw.pyotgw.connect", return_value=MINIMAL_STATUS_UPD):
+        await setup.async_setup_component(hass, DOMAIN, {})
+
+    await hass.async_block_till_done()
+    gw_dev = dev_reg.async_get_device(
+        identifiers={(DOMAIN, MOCK_GATEWAY_ID)}, connections=set()
+    )
+    assert gw_dev.sw_version == VERSION_NEW