diff -r 87509d71653b Lib/inspect.py
--- a/Lib/inspect.py	Wed May 27 11:08:46 2015 -0400
+++ b/Lib/inspect.py	Wed May 27 15:58:33 2015 -0400
@@ -2129,7 +2129,17 @@
 
     # Was this function wrapped by a decorator?
     if follow_wrapper_chains:
-        obj = unwrap(obj, stop=(lambda f: hasattr(f, "__signature__")))
+        obj = unwrap(obj, stop=(lambda f: hasattr(f, "__signature__") or
+                                          isinstance(f, types.MethodType)))
+        if isinstance(obj, types.MethodType):
+            # If during unwrapping we've encountered a decorated *method*,
+            # we might want to skip its first parameter (self).
+            # See test_signature_wrapped_bound_method for details.
+            return _signature_from_callable(
+                obj,
+                follow_wrapper_chains=follow_wrapper_chains,
+                skip_bound_arg=skip_bound_arg,
+                sigcls=sigcls)
 
     try:
         sig = obj.__signature__
diff -r 87509d71653b Lib/test/test_inspect.py
--- a/Lib/test/test_inspect.py	Wed May 27 11:08:46 2015 -0400
+++ b/Lib/test/test_inspect.py	Wed May 27 15:58:33 2015 -0400
@@ -2086,6 +2086,19 @@
         with self.assertRaisesRegex(ValueError, 'invalid method signature'):
             self.signature(Test())
 
+    def test_signature_wrapped_bound_method(self):
+        # Issue 24298
+        class Test:
+            def m1(self, arg1, arg2=1) -> int:
+                pass
+        @functools.wraps(Test().m1)
+        def m1d(*args, **kwargs):
+            pass
+        self.assertEqual(self.signature(m1d),
+                         ((('arg1', ..., ..., "positional_or_keyword"),
+                           ('arg2', 1, ..., "positional_or_keyword")),
+                          int))
+
     def test_signature_on_classmethod(self):
         class Test:
             @classmethod