diff --git a/src/bedrock_agentcore/memory/integrations/strands/session_manager.py b/src/bedrock_agentcore/memory/integrations/strands/session_manager.py
index 3cbe3aa..4f69618 100644
--- a/src/bedrock_agentcore/memory/integrations/strands/session_manager.py
+++ b/src/bedrock_agentcore/memory/integrations/strands/session_manager.py
@@ -2,6 +2,7 @@
 
 import json
 import logging
+import os
 from datetime import datetime, timezone
 from typing import TYPE_CHECKING, Any, Optional
 
@@ -64,6 +65,7 @@ def __init__(
                Defaults to None.
             **kwargs (Any): Additional keyword arguments.
         """
+        region_name = region_name or os.environ.get("AWS_REGION")
         self.config = agentcore_memory_config
         self.memory_client = MemoryClient(region_name=region_name)
         session = boto_session or boto3.Session(region_name=region_name)
diff --git a/tests/bedrock_agentcore/memory/integrations/strands/test_agentcore_memory_session_manager.py b/tests/bedrock_agentcore/memory/integrations/strands/test_agentcore_memory_session_manager.py
index 46b68fe..9ba0e91 100644
--- a/tests/bedrock_agentcore/memory/integrations/strands/test_agentcore_memory_session_manager.py
+++ b/tests/bedrock_agentcore/memory/integrations/strands/test_agentcore_memory_session_manager.py
@@ -99,6 +99,24 @@ def test_init_basic(self, agentcore_config):
                     assert manager.memory_client == mock_client
                     mock_client_class.assert_called_once_with(region_name=None)
 
+    def test_init_with_aws_region_env_var(self, agentcore_config):
+        """Test initialization with AWS_REGION environment variable."""
+        with patch("bedrock_agentcore.memory.integrations.strands.session_manager.MemoryClient") as mock_client_class:
+            mock_client = Mock()
+            mock_client_class.return_value = mock_client
+
+            with patch("boto3.Session") as mock_boto_session:
+                mock_session = Mock()
+                mock_session.client.return_value = Mock()
+                mock_boto_session.return_value = mock_session
+
+                with patch(
+                    "strands.session.repository_session_manager.RepositorySessionManager.__init__", return_value=None
+                ):
+                    with patch.dict("os.environ", {"AWS_REGION": "us-east-1"}):
+                        AgentCoreMemorySessionManager(agentcore_config)
+                        mock_client_class.assert_called_once_with(region_name="us-east-1")
+
     def test_events_to_messages(self, session_manager):
         """Test converting Bedrock events to SessionMessages."""
         events = [