diff --git a/homeassistant/helpers/llm.py b/homeassistant/helpers/llm.py
index 5d9e4c3bdef..bf89e693870 100644
--- a/homeassistant/helpers/llm.py
+++ b/homeassistant/helpers/llm.py
@@ -777,7 +777,23 @@ def _selector_serializer(schema: Any) -> Any:  # noqa: C901
         return result
 
     if isinstance(schema, selector.ObjectSelector):
-        return {"type": "object", "additionalProperties": True}
+        result = {"type": "object"}
+        if fields := schema.config.get("fields"):
+            result["properties"] = {
+                field: convert(
+                    selector.selector(field_schema["selector"]),
+                    custom_serializer=_selector_serializer,
+                )
+                for field, field_schema in fields.items()
+            }
+        else:
+            result["additionalProperties"] = True
+        if schema.config.get("multiple"):
+            result = {
+                "type": "array",
+                "items": result,
+            }
+        return result
 
     if isinstance(schema, selector.SelectSelector):
         options = [
diff --git a/tests/helpers/test_llm.py b/tests/helpers/test_llm.py
index b6894505534..b978559130c 100644
--- a/tests/helpers/test_llm.py
+++ b/tests/helpers/test_llm.py
@@ -1139,6 +1139,59 @@ async def test_selector_serializer(
         "type": "object",
         "additionalProperties": True,
     }
+    assert selector_serializer(
+        selector.ObjectSelector(
+            {
+                "fields": {
+                    "name": {
+                        "required": True,
+                        "selector": {"text": {}},
+                    },
+                    "percentage": {
+                        "selector": {"number": {"min": 30, "max": 100}},
+                    },
+                },
+                "multiple": False,
+                "label_field": "name",
+            },
+        )
+    ) == {
+        "type": "object",
+        "properties": {
+            "name": {"type": "string"},
+            "percentage": {"type": "number", "minimum": 30, "maximum": 100},
+        },
+    }
+    assert selector_serializer(
+        selector.ObjectSelector(
+            {
+                "fields": {
+                    "name": {
+                        "required": True,
+                        "selector": {"text": {}},
+                    },
+                    "percentage": {
+                        "selector": {"number": {"min": 30, "max": 100}},
+                    },
+                },
+                "multiple": True,
+                "label_field": "name",
+            },
+        )
+    ) == {
+        "type": "array",
+        "items": {
+            "type": "object",
+            "properties": {
+                "name": {"type": "string"},
+                "percentage": {
+                    "type": "number",
+                    "minimum": 30,
+                    "maximum": 100,
+                },
+            },
+        },
+    }
     assert selector_serializer(
         selector.SelectSelector(
             {