diff --git a/test/test_serialization.py b/test/test_serialization.py
index 59d6e21bd3a..4e1a1a8e49d 100644
--- a/test/test_serialization.py
+++ b/test/test_serialization.py
@@ -16,6 +16,7 @@ import warnings
 import zipfile
 from collections import namedtuple, OrderedDict
 from copy import deepcopy
+from dataclasses import dataclass
 from itertools import product
 from pathlib import Path
 
@@ -844,6 +845,17 @@ class ClassThatUsesBuildInstruction:
         # Third item, state here will cause pickle to push a BUILD instruction
         return ClassThatUsesBuildInstruction, (self.num,), {'foo': 'bar'}
 
+@dataclass
+class ClassThatUsesBuildInstructionAllSlots:
+    __slots__ = ["x", "y"]
+    x: int
+    y: int
+
+@dataclass
+class ClassThatUsesBuildInstructionSomeSlots(ClassThatUsesBuildInstructionAllSlots):
+    x: int
+    y: int
+    c: str
 
 @unittest.skipIf(IS_WINDOWS, "NamedTemporaryFile on windows")
 class TestBothSerialization(TestCase):
@@ -1142,6 +1154,25 @@ class TestSerialization(TestCase, SerializationMixin):
                 torch.serialization.clear_safe_globals()
                 ClassThatUsesBuildInstruction.__setstate__ = None
 
+    @parametrize("slots", ['some', 'all'])
+    def test_weights_only_safe_globals_build_with_slots(self, slots):
+        obj_cls = (
+            ClassThatUsesBuildInstructionAllSlots if slots == 'all' else ClassThatUsesBuildInstructionSomeSlots
+        )
+        args = (2, 3) if slots == 'all' else (2, 3, 'foo')
+        obj = obj_cls(*args)
+        with BytesIOContext() as f:
+            torch.save(obj, f)
+            f.seek(0)
+            with self.assertRaisesRegex(pickle.UnpicklingError,
+                                        f"GLOBAL __main__.{obj_cls.__name__} was not an allowed global by default"):
+                torch.load(f, weights_only=True)
+
+            f.seek(0)
+            with torch.serialization.safe_globals([obj_cls]):
+                loaded_obj = torch.load(f, weights_only=True)
+                self.assertEqual(loaded_obj, obj)
+
     def test_weights_only_safe_globals_blocklist(self):
         module = 'nt' if IS_WINDOWS else 'posix'
         error_msg = f"unsupported GLOBAL {module}.execv whose module {module} is blocked"
diff --git a/torch/_weights_only_unpickler.py b/torch/_weights_only_unpickler.py
index 918db8ba0be..eb6072971ec 100644
--- a/torch/_weights_only_unpickler.py
+++ b/torch/_weights_only_unpickler.py
@@ -292,6 +292,13 @@ class Unpickler:
                 elif type(inst) in _get_user_allowed_globals().values():
                     if hasattr(inst, "__setstate__"):
                         inst.__setstate__(state)
+                    elif hasattr(inst, "__slots__"):
+                        # if slots are defined, state will be a tuple (state, slotstate)
+                        state, slotstate = state
+                        for k, v in slotstate.items():
+                            setattr(inst, k, v)
+                        if state:
+                            inst.__dict__.update(state)
                     else:
                         inst.__dict__.update(state)
                 else: