diff --git a/README.md b/README.md
index 56bd976..af3d7cb 100644
--- a/README.md
+++ b/README.md
@@ -343,6 +343,24 @@ A DSVError is raised with 3 errors in args.
 
 """
 ```
+---
+### Feature: Self-defined Spec name in error message
+```python
+from data_spec_validator.spec import Checker, dsv_feature, validate_data_spec, INT
+
+@dsv_feature(spec_name='CustomSpecName')
+class _MySpec:
+    a = Checker([INT])
+
+nok_data = dict(
+    a='abc',
+)
+
+validate_data_spec(nok_data, _MySpec)
+"""
+TypeError: field: CustomSpecName.a, reason: 'abc' is not an integer
+"""
+```
 
 ---
 ## Test
diff --git a/data_spec_validator/spec/defines.py b/data_spec_validator/spec/defines.py
index 9bf8ee6..ffd0dc4 100644
--- a/data_spec_validator/spec/defines.py
+++ b/data_spec_validator/spec/defines.py
@@ -76,8 +76,10 @@ def __str__(self, *args, **kwargs):
 
 class ValidateResult:
     def __init__(self, spec: Type = None, field: str = None, value: Any = None, check: str = None, error=None):
+        from .features import get_spec_name  # FIXME: refine the structure to avoid circular import
+
         # TODO: Output spec & check information when there's a debug message level for development.
-        self.__spec = spec.__name__ if spec else None
+        self.__spec = get_spec_name(spec) if spec else None
         self.__field = field
         self.__value = value
         self.__check = check
diff --git a/data_spec_validator/spec/features.py b/data_spec_validator/spec/features.py
index 4f90402..80524a7 100644
--- a/data_spec_validator/spec/features.py
+++ b/data_spec_validator/spec/features.py
@@ -5,12 +5,13 @@
 
 
 class _DSVFeatureParams:
-    __slots__ = ('_strict', '_any_keys_set', '_err_mode')
+    __slots__ = ('_strict', '_any_keys_set', '_err_mode', '_spec_name')
 
-    def __init__(self, strict, any_keys_set: Union[Set[Tuple[str, ...]], None], err_mode):
+    def __init__(self, strict, any_keys_set: Union[Set[Tuple[str, ...]], None], err_mode, spec_name):
         self._strict = strict
         self._any_keys_set = any_keys_set or set()
         self._err_mode = err_mode
+        self._spec_name = spec_name
 
     @property
     def err_mode(self) -> ErrorMode:
@@ -24,30 +25,45 @@ def strict(self) -> bool:
     def any_keys_set(self) -> set:
         return self._any_keys_set
 
+    @property
+    def spec_name(self) -> str:
+        return self._spec_name
+
     def __repr__(self):
-        return f'_DSVFeatureParams(strict={self._strict}, any_keys_set={self._any_keys_set}, err_mode={self._err_mode})'
+        return f'_DSVFeatureParams(strict={self._strict}, any_keys_set={self._any_keys_set}, err_mode={self._err_mode}), spec_name={self._spec_name}'
 
 
 _FEAT_PARAMS = '__feat_params__'
 
 
 def _process_class(
-    cls: Type, strict: bool, any_keys_set: Union[Set[Tuple[str, ...]], None], err_mode: ErrorMode
+    cls: Type,
+    strict: bool,
+    any_keys_set: Union[Set[Tuple[str, ...]], None],
+    err_mode: ErrorMode,
+    spec_name: Optional[str],
 ) -> Type:
-    setattr(cls, _FEAT_PARAMS, _DSVFeatureParams(strict, any_keys_set, err_mode))
+    setattr(cls, _FEAT_PARAMS, _DSVFeatureParams(strict, any_keys_set, err_mode, spec_name))
 
     return cls
 
 
 def dsv_feature(
-    strict: bool = False, any_keys_set: Optional[Set[Tuple[str, ...]]] = None, err_mode=ErrorMode.MSE
+    strict: bool = False,
+    any_keys_set: Optional[Set[Tuple[str, ...]]] = None,
+    err_mode=ErrorMode.MSE,
+    spec_name: Optional[str] = None,
 ) -> Callable:
     def wrap(cls: Type) -> Type:
-        return _process_class(cls, strict, any_keys_set, err_mode)
+        return _process_class(cls, strict, any_keys_set, err_mode, spec_name)
 
     return wrap
 
 
+def get_spec_name(spec) -> str:
+    return getattr(spec, _FEAT_PARAMS).spec_name if hasattr(spec, _FEAT_PARAMS) else spec.__name__
+
+
 def get_err_mode(spec) -> ErrorMode:
     feat_params: Union[_DSVFeatureParams, None] = getattr(spec, _FEAT_PARAMS, None)
     return feat_params.err_mode if feat_params else ErrorMode.MSE
diff --git a/test/test_nested_spec.py b/test/test_nested_spec.py
index d43d340..5138a31 100644
--- a/test/test_nested_spec.py
+++ b/test/test_nested_spec.py
@@ -1,6 +1,7 @@
 import unittest
 
-from data_spec_validator.spec import BOOL, DICT, DIGIT_STR, FLOAT, INT, NONE, SPEC, STR, Checker, validate_data_spec
+from data_spec_validator.spec import BOOL, DICT, DIGIT_STR, FLOAT, INT, NONE, SPEC, STR, Checker, validate_data_spec, \
+    dsv_feature
 
 from .utils import is_something_error
 
@@ -61,3 +62,28 @@ class ChildSpec3:
             c3_f=[],
         )
         assert is_something_error(TypeError, validate_data_spec, nok_data, NestedSpec)
+
+    def test_nested_error_field_name(self):
+        class NestedSpec:
+            class ChildSpec1:
+                @dsv_feature(spec_name='NestedSpec.c1_f.s_1')
+                class ChildSpec11:
+                    f_11 = Checker([FLOAT])
+
+                s_1 = Checker([SPEC], SPEC=ChildSpec11)
+
+            c1_f = Checker([SPEC], SPEC=ChildSpec1)
+
+        nok_data = dict(
+            c1_f=dict(
+                s_1=dict(
+                    f_11=None,
+                ),
+            ),
+        )
+
+        with self.assertRaises(TypeError) as exc_info:
+            validate_data_spec(nok_data, NestedSpec)
+
+        exc_msg = str(exc_info.exception)
+        self.assertEqual(exc_msg, 'field: NestedSpec.c1_f.s_1.f_11, reason: None is not a float')