Index: Objects/descrobject.c
===================================================================
--- Objects/descrobject.c	(revision 72178)
+++ Objects/descrobject.c	(working copy)
@@ -1288,9 +1288,23 @@
 	if ((doc == NULL || doc == Py_None) && get != NULL) {
 		PyObject *get_doc = PyObject_GetAttrString(get, "__doc__");
 		if (get_doc != NULL) {
-			Py_XDECREF(prop->prop_doc);
-			prop->prop_doc = get_doc;  /* get_doc already INCREF'd by GetAttr */
-			prop->getter_doc = 1;
+			/* get_doc already INCREF'd by GetAttr */
+			if (Py_TYPE(self)==&PyProperty_Type) {
+				Py_XDECREF(prop->prop_doc);
+				prop->prop_doc = get_doc;
+				prop->getter_doc = 1;
+			} else {
+				/* Put __doc__ in dict of the subclass instance instead,
+				otherwise it gets shadowed by class's __doc__. */
+				if (PyObject_SetAttrString(self, "__doc__", get_doc) != 0)
+	                        {
+	                        	Py_XDECREF(get);
+	                        	Py_XDECREF(set);
+	                        	Py_XDECREF(del);
+	                        	Py_XDECREF(doc);
+	                        	return -1;
+	                        }
+			}
 		} else {
 			PyErr_Clear();
 		}
Index: Lib/test/test_property.py
===================================================================
--- Lib/test/test_property.py	(revision 72149)
+++ Lib/test/test_property.py	(working copy)
@@ -91,8 +91,30 @@
         self.assertEqual(base.__class__.spam.__doc__, "spam spam spam")
         self.assertEqual(sub.__class__.spam.__doc__, "spam spam spam")
 
+class PropertySub(property):
+    """This is a subclass of property"""
+
+
+# Issue 5890: subclasses of property do not preserve method __doc__ strings
+class PSBaseClass(object):
+
+    @PropertySub
+    def spam(self):
+        """spam wrapped in a property subclass"""
+        return 1
+
+
+class PropertySubclassTests(unittest.TestCase):
+
+    def test_docstring(self):
+        base = PSBaseClass()
+        self.assertEqual(
+            base.__class__.spam.__doc__,
+            "spam wrapped in a property subclass")
+
+
 def test_main():
-    run_unittest(PropertyTests)
+    run_unittest(PropertyTests, PropertySubclassTests)
 
 if __name__ == '__main__':
     test_main()