diff --git a/backend/apps/system/api/aimodel.py b/backend/apps/system/api/aimodel.py
index bf7bf1f4..3280d96f 100644
--- a/backend/apps/system/api/aimodel.py
+++ b/backend/apps/system/api/aimodel.py
@@ -29,7 +29,7 @@ async def check_llm(info: AiModelCreator, trans: Trans):
     async def generate():
         try:
             additional_params = {item.key: prepare_model_arg(item.val) for item in info.config_list if
-                                 item.key and item.val}
+                                 item.key and item.val is not None and item.val != ""}
             config = LLMConfig(
                 model_type="openai" if info.protocol == 1 else "vllm",
                 model_name=info.base_model,
diff --git a/backend/tests/test_model_validation_parameters.py b/backend/tests/test_model_validation_parameters.py
new file mode 100644
index 00000000..dae2e591
--- /dev/null
+++ b/backend/tests/test_model_validation_parameters.py
@@ -0,0 +1,143 @@
+"""Execute model validation with real DTOs and no provider/database connections."""
+
+import ast
+import asyncio
+import json
+from pathlib import Path
+from types import SimpleNamespace
+from typing import Any, Optional
+from unittest.mock import Mock
+
+import pytest
+from fastapi.responses import StreamingResponse
+from pydantic import BaseModel, Field
+
+BACKEND_DIR = Path(__file__).resolve().parents[1]
+
+
+def load_symbol(path, name, namespace):
+    source = BACKEND_DIR / path
+    tree = ast.parse(source.read_text(encoding="utf-8"))
+    node = next(node for node in tree.body if getattr(node, "name", None) == name)
+    # Keep production handler logic while isolating unrelated auth/DB imports.
+    if isinstance(node, ast.AsyncFunctionDef):
+        node.decorator_list = []
+    exec(
+        compile(ast.Module(body=[node], type_ignores=[]), str(source), "exec"),
+        namespace,
+    )
+    return namespace[name]
+
+
+@pytest.fixture
+def validation():
+    namespace = {
+        "BaseModel": BaseModel,
+        "Field": Field,
+        "List": list,
+        "Dict": dict,
+        "Any": Any,
+        "Optional": Optional,
+        "PLACEHOLDER_PREFIX": "PLACEHOLDER_",
+        "json": json,
+        "Trans": object,
+        "StreamingResponse": StreamingResponse,
+        "SQLBotLogUtil": Mock(),
+    }
+    schema = "apps/system/schemas/ai_model_schema.py"
+    for name in ("AiModelItem", "AiModelConfigItem", "AiModelCreator"):
+        load_symbol(schema, name, namespace)
+    load_symbol("common/utils/utils.py", "prepare_model_arg", namespace)
+    load_symbol("apps/ai_model/model_factory.py", "LLMConfig", namespace)
+
+    async def stream(_question):
+        yield "ok"
+
+    factory = Mock()
+    factory.create_llm.return_value = SimpleNamespace(
+        llm=SimpleNamespace(astream=stream)
+    )
+    namespace["LLMFactory"] = factory
+    handler = load_symbol("apps/system/api/aimodel.py", "check_llm", namespace)
+
+    def run(rows):
+        info = namespace["AiModelCreator"](
+            name="test",
+            model_type=0,
+            base_model="test",
+            supplier=15,
+            protocol=1,
+            api_domain="https://example.test/v1",
+            api_key="test-key",
+            config_list=rows,
+        )
+
+        async def consume():
+            response = await handler(info, lambda key, **_kwargs: key)
+            assert isinstance(response, StreamingResponse)
+            return [json.loads(chunk) async for chunk in response.body_iterator]
+
+        assert asyncio.run(consume()) == [{"content": "ok"}]
+        factory.create_llm.assert_called_once()
+        return factory.create_llm.call_args.args[0].additional_params
+
+    return run
+
+
+@pytest.mark.parametrize("value", [0, 0.0, False])
+def test_validation_preserves_zero_and_false(validation, value):
+    result = validation(
+        [
+            {"key": "sample", "val": value, "name": "sample"},
+            {"key": "max_tokens", "val": 1024, "name": "tokens"},
+        ]
+    )
+    assert result == {"sample": value, "max_tokens": 1024}
+    assert type(result["sample"]) is type(value)
+
+
+@pytest.mark.parametrize("value", [1, 0.5, True, "0", "false", "text", [], {}])
+def test_validation_preserves_other_supplied_values(validation, value):
+    result = validation([{"key": "sample", "val": value, "name": "sample"}])
+    assert result == {"sample": value}
+    assert type(result["sample"]) is type(value)
+
+
+@pytest.mark.parametrize("value", [None, ""])
+def test_validation_still_skips_absent_values(validation, value):
+    assert validation([{"key": "sample", "val": value, "name": "sample"}]) == {}
+
+
+def test_validation_still_skips_empty_keys(validation):
+    assert validation([{"key": "", "val": 1, "name": "sample"}]) == {}
+
+
+@pytest.mark.parametrize(
+    "value, expected",
+    [
+        ('{"enable_thinking": false}', {"enable_thinking": False}),
+        ('["stop"]', ["stop"]),
+        ('{"invalid"', '{"invalid"'),
+    ],
+)
+def test_validation_keeps_json_conversion(validation, value, expected):
+    assert validation([{"key": "sample", "val": value, "name": "sample"}]) == {
+        "sample": expected,
+    }
+
+
+def test_validation_mixed_configuration(validation):
+    assert validation(
+        [
+            {"key": "temperature", "val": 0, "name": "temperature"},
+            {"key": "stream_usage", "val": False, "name": "stream_usage"},
+            {"key": "max_tokens", "val": 1024, "name": "tokens"},
+            {"key": "extra_body", "val": '{"enable_thinking": false}', "name": "extra"},
+            {"key": "omitted", "val": None, "name": "omitted"},
+        ]
+    ) == {
+        "temperature": 0,
+        "stream_usage": False,
+        "max_tokens": 1024,
+        "extra_body": {"enable_thinking": False},
+    }