diff --git a/opentelemetry-sdk/src/opentelemetry/sdk/trace/__init__.py b/opentelemetry-sdk/src/opentelemetry/sdk/trace/__init__.py
index c1389594a38..c162ea5c1ca 100644
--- a/opentelemetry-sdk/src/opentelemetry/sdk/trace/__init__.py
+++ b/opentelemetry-sdk/src/opentelemetry/sdk/trace/__init__.py
@@ -20,7 +20,7 @@
 import threading
 from contextlib import contextmanager
 from types import TracebackType
-from typing import Iterator, Optional, Sequence, Tuple, Type
+from typing import Iterator, MutableSequence, Optional, Sequence, Tuple, Type
 
 from opentelemetry import context as context_api
 from opentelemetry import trace as trace_api
@@ -314,6 +314,9 @@ def set_attribute(self, key: str, value: types.AttributeValue) -> None:
             if error_message is not None:
                 logger.warning("%s in attribute value sequence", error_message)
                 return
+            # Freeze mutable sequences defensively
+            if isinstance(value, MutableSequence):
+                value = tuple(value)
         elif not isinstance(value, (bool, str, int, float)):
             logger.warning("invalid type for attribute value")
             return
diff --git a/opentelemetry-sdk/tests/trace/test_trace.py b/opentelemetry-sdk/tests/trace/test_trace.py
index 4781c7cf805..ccb1ccd1e4e 100644
--- a/opentelemetry-sdk/tests/trace/test_trace.py
+++ b/opentelemetry-sdk/tests/trace/test_trace.py
@@ -412,8 +412,10 @@ def test_attributes(self):
             root.set_attribute("attr-key", "attr-value2")
 
             root.set_attribute("empty-list", [])
-            root.set_attribute("list-of-bools", [True, True, False])
-            root.set_attribute("list-of-numerics", [123, 314, 0])
+            list_of_bools = [True, True, False]
+            root.set_attribute("list-of-bools", list_of_bools)
+            list_of_numerics = [123, 314, 0]
+            root.set_attribute("list-of-numerics", list_of_numerics)
 
             self.assertEqual(len(root.attributes), 10)
             self.assertEqual(root.attributes["component"], "http")
@@ -426,12 +428,20 @@ def test_attributes(self):
             self.assertEqual(root.attributes["http.status_text"], "OK")
             self.assertEqual(root.attributes["misc.pi"], 3.14)
             self.assertEqual(root.attributes["attr-key"], "attr-value2")
-            self.assertEqual(root.attributes["empty-list"], [])
+            self.assertEqual(root.attributes["empty-list"], ())
             self.assertEqual(
-                root.attributes["list-of-bools"], [True, True, False]
+                root.attributes["list-of-bools"], (True, True, False)
             )
+            list_of_bools.append(False)
             self.assertEqual(
-                root.attributes["list-of-numerics"], [123, 314, 0]
+                root.attributes["list-of-bools"], (True, True, False)
+            )
+            self.assertEqual(
+                root.attributes["list-of-numerics"], (123, 314, 0)
+            )
+            list_of_numerics.append(227)
+            self.assertEqual(
+                root.attributes["list-of-numerics"], (123, 314, 0)
             )
 
         attributes = {