diff --git a/tests/unit/domain/test_tts_config.py b/tests/unit/domain/test_tts_config.py
new file mode 100755
index 000000000..7cdad3bd8
--- /dev/null
+++ b/tests/unit/domain/test_tts_config.py
@@ -0,0 +1,314 @@
+"""TtsConfig 单元测试."""
+
+from __future__ import annotations
+
+import pytest
+from domain.tts_config import TtsConfig
+
+
+class TestTtsConfigDefaults:
+    """默认值测试."""
+
+    def test_default_values(self):
+        config = TtsConfig()
+        assert config.enabled is False
+        assert config.voice_id == ""
+        assert config.speed == 1.0
+        assert config.pitch == 0.0
+        assert config.volume == 0.8
+        assert config.text == ""
+        assert config.align_mode == "full"
+        assert config.overlap_mode == "replace"
+
+    def test_custom_construction(self):
+        config = TtsConfig(
+            enabled=True,
+            voice_id="voice_001",
+            speed=1.5,
+            pitch=3.0,
+            volume=0.9,
+            text="hello",
+            align_mode="subtitle",
+            overlap_mode="mix",
+        )
+        assert config.enabled is True
+        assert config.voice_id == "voice_001"
+        assert config.speed == 1.5
+        assert config.pitch == 3.0
+        assert config.volume == 0.9
+        assert config.text == "hello"
+        assert config.align_mode == "subtitle"
+        assert config.overlap_mode == "mix"
+
+    def test_slots_no_extra_attrs(self):
+        config = TtsConfig()
+        with pytest.raises((AttributeError, TypeError)):
+            config.new_attr = "value"  # type: ignore[attr-defined]
+
+    def test_equality_same_values(self):
+        a = TtsConfig(enabled=True, voice_id="v1")
+        b = TtsConfig(enabled=True, voice_id="v1")
+        assert a == b
+
+    def test_equality_different_values(self):
+        a = TtsConfig(enabled=True)
+        b = TtsConfig(enabled=False)
+        assert a != b
+
+
+class TestTtsConfigParseNoneAndEmpty:
+    """parse 空输入测试."""
+
+    def test_parse_none(self):
+        config = TtsConfig.parse(None)
+        assert config == TtsConfig()
+
+    def test_parse_empty_dict(self):
+        config = TtsConfig.parse({})
+        assert config == TtsConfig()
+
+    def test_parse_non_dict_string(self):
+        config = TtsConfig.parse("not a dict")  # type: ignore[arg-type]
+        assert config == TtsConfig()
+
+    def test_parse_non_dict_list(self):
+        config = TtsConfig.parse([])  # type: ignore[arg-type]
+        assert config == TtsConfig()
+
+    def test_parse_non_dict_number(self):
+        config = TtsConfig.parse(123)  # type: ignore[arg-type]
+        assert config == TtsConfig()
+
+
+class TestTtsConfigParseDisabled:
+    """parse disabled 场景."""
+
+    def test_parse_enabled_false_returns_default(self):
+        config = TtsConfig.parse({"enabled": False})
+        assert config.enabled is False
+        assert config.speed == 1.0
+        assert config.voice_id == ""
+
+    def test_parse_enabled_false_ignores_other_fields(self):
+        config = TtsConfig.parse(
+            {
+                "enabled": False,
+                "voice_id": "v1",
+                "speed": 1.5,
+            }
+        )
+        assert config.enabled is False
+        assert config.voice_id == ""
+        assert config.speed == 1.0
+
+    def test_parse_enabled_non_bool_falls_to_false(self):
+        config = TtsConfig.parse({"enabled": "true"})
+        assert config.enabled is False
+
+    def test_parse_enabled_int_falls_to_false(self):
+        config = TtsConfig.parse({"enabled": 1})
+        assert config.enabled is False
+
+
+class TestTtsConfigParseNormal:
+    """parse 正常数据测试."""
+
+    def test_parse_full_data(self):
+        data = {
+            "enabled": True,
+            "voice_id": "voice_001",
+            "speed": 1.5,
+            "pitch": 2.5,
+            "volume": 0.7,
+            "text": "你好世界",
+            "align_mode": "subtitle",
+            "overlap_mode": "mix",
+        }
+        config = TtsConfig.parse(data)
+        assert config.enabled is True
+        assert config.voice_id == "voice_001"
+        assert config.speed == 1.5
+        assert config.pitch == 2.5
+        assert config.volume == 0.7
+        assert config.text == "你好世界"
+        assert config.align_mode == "subtitle"
+        assert config.overlap_mode == "mix"
+
+    def test_parse_int_speed_becomes_float(self):
+        config = TtsConfig.parse({"enabled": True, "speed": 2})
+        assert isinstance(config.speed, float)
+        assert config.speed == 2.0
+
+    def test_parse_int_pitch_becomes_float(self):
+        config = TtsConfig.parse({"enabled": True, "pitch": -3})
+        assert isinstance(config.pitch, float)
+        assert config.pitch == -3.0
+
+
+class TestTtsConfigParseTypeFallback:
+    """parse 类型错误回退测试."""
+
+    def test_parse_voice_id_non_string_fallback(self):
+        config = TtsConfig.parse({"enabled": True, "voice_id": 123})
+        assert config.voice_id == ""
+
+    def test_parse_speed_non_numeric_fallback(self):
+        config = TtsConfig.parse({"enabled": True, "speed": "fast"})
+        assert config.speed == 1.0
+
+    def test_parse_pitch_non_numeric_fallback(self):
+        config = TtsConfig.parse({"enabled": True, "pitch": "high"})
+        assert config.pitch == 0.0
+
+    def test_parse_volume_non_numeric_fallback(self):
+        config = TtsConfig.parse({"enabled": True, "volume": "loud"})
+        assert config.volume == 0.8
+
+    def test_parse_text_non_string_fallback(self):
+        config = TtsConfig.parse({"enabled": True, "text": 456})
+        assert config.text == ""
+
+    def test_parse_voice_id_list_fallback(self):
+        config = TtsConfig.parse({"enabled": True, "voice_id": ["v1"]})
+        assert config.voice_id == ""
+
+
+class TestTtsConfigParseClamp:
+    """parse 边界钳制测试."""
+
+    def test_parse_speed_below_min_clamped(self):
+        config = TtsConfig.parse({"enabled": True, "speed": 0.1})
+        assert config.speed == 0.5
+
+    def test_parse_speed_above_max_clamped(self):
+        config = TtsConfig.parse({"enabled": True, "speed": 3.0})
+        assert config.speed == 2.0
+
+    def test_parse_speed_at_min_ok(self):
+        config = TtsConfig.parse({"enabled": True, "speed": 0.5})
+        assert config.speed == 0.5
+
+    def test_parse_speed_at_max_ok(self):
+        config = TtsConfig.parse({"enabled": True, "speed": 2.0})
+        assert config.speed == 2.0
+
+    def test_parse_pitch_below_min_clamped(self):
+        config = TtsConfig.parse({"enabled": True, "pitch": -20})
+        assert config.pitch == -12
+
+    def test_parse_pitch_above_max_clamped(self):
+        config = TtsConfig.parse({"enabled": True, "pitch": 20})
+        assert config.pitch == 12
+
+    def test_parse_pitch_at_min_ok(self):
+        config = TtsConfig.parse({"enabled": True, "pitch": -12})
+        assert config.pitch == -12
+
+    def test_parse_pitch_at_max_ok(self):
+        config = TtsConfig.parse({"enabled": True, "pitch": 12})
+        assert config.pitch == 12
+
+    def test_parse_volume_below_min_clamped(self):
+        config = TtsConfig.parse({"enabled": True, "volume": -0.5})
+        assert config.volume == 0.0
+
+    def test_parse_volume_above_max_clamped(self):
+        config = TtsConfig.parse({"enabled": True, "volume": 1.5})
+        assert config.volume == 1.0
+
+    def test_parse_volume_at_min_ok(self):
+        config = TtsConfig.parse({"enabled": True, "volume": 0.0})
+        assert config.volume == 0.0
+
+    def test_parse_volume_at_max_ok(self):
+        config = TtsConfig.parse({"enabled": True, "volume": 1.0})
+        assert config.volume == 1.0
+
+
+class TestTtsConfigParseAlignMode:
+    """align_mode 解析测试."""
+
+    def test_parse_align_mode_subtitle(self):
+        config = TtsConfig.parse({"enabled": True, "align_mode": "subtitle"})
+        assert config.align_mode == "subtitle"
+
+    def test_parse_align_mode_full(self):
+        config = TtsConfig.parse({"enabled": True, "align_mode": "full"})
+        assert config.align_mode == "full"
+
+    def test_parse_align_mode_invalid_fallback(self):
+        config = TtsConfig.parse({"enabled": True, "align_mode": "auto"})
+        assert config.align_mode == "full"
+
+    def test_parse_align_mode_empty_fallback(self):
+        config = TtsConfig.parse({"enabled": True, "align_mode": ""})
+        assert config.align_mode == "full"
+
+
+class TestTtsConfigParseOverlapMode:
+    """overlap_mode 解析测试."""
+
+    def test_parse_overlap_mode_replace(self):
+        config = TtsConfig.parse({"enabled": True, "overlap_mode": "replace"})
+        assert config.overlap_mode == "replace"
+
+    def test_parse_overlap_mode_mix(self):
+        config = TtsConfig.parse({"enabled": True, "overlap_mode": "mix"})
+        assert config.overlap_mode == "mix"
+
+    def test_parse_overlap_mode_invalid_fallback(self):
+        config = TtsConfig.parse({"enabled": True, "overlap_mode": "add"})
+        assert config.overlap_mode == "replace"
+
+    def test_parse_overlap_mode_empty_fallback(self):
+        config = TtsConfig.parse({"enabled": True, "overlap_mode": ""})
+        assert config.overlap_mode == "replace"
+
+
+class TestTtsConfigClamp:
+    """_clamp 直接调用测试."""
+
+    def test_clamp_speed_low(self):
+        config = TtsConfig(enabled=True, speed=0.1)
+        config._clamp()
+        assert config.speed == 0.5
+
+    def test_clamp_speed_high(self):
+        config = TtsConfig(enabled=True, speed=5.0)
+        config._clamp()
+        assert config.speed == 2.0
+
+    def test_clamp_speed_normal_unchanged(self):
+        config = TtsConfig(enabled=True, speed=1.2)
+        config._clamp()
+        assert config.speed == 1.2
+
+    def test_clamp_pitch_low(self):
+        config = TtsConfig(enabled=True, pitch=-20)
+        config._clamp()
+        assert config.pitch == -12
+
+    def test_clamp_pitch_high(self):
+        config = TtsConfig(enabled=True, pitch=20)
+        config._clamp()
+        assert config.pitch == 12
+
+    def test_clamp_pitch_normal_unchanged(self):
+        config = TtsConfig(enabled=True, pitch=5.0)
+        config._clamp()
+        assert config.pitch == 5.0
+
+    def test_clamp_volume_low(self):
+        config = TtsConfig(enabled=True, volume=-1.0)
+        config._clamp()
+        assert config.volume == 0.0
+
+    def test_clamp_volume_high(self):
+        config = TtsConfig(enabled=True, volume=2.0)
+        config._clamp()
+        assert config.volume == 1.0
+
+    def test_clamp_volume_normal_unchanged(self):
+        config = TtsConfig(enabled=True, volume=0.5)
+        config._clamp()
+        assert config.volume == 0.5