diff --git a/alts/src/main/java/io/grpc/alts/internal/AltsProtocolNegotiator.java b/alts/src/main/java/io/grpc/alts/internal/AltsProtocolNegotiator.java
index 52e96ccedd..edb38000dd 100644
--- a/alts/src/main/java/io/grpc/alts/internal/AltsProtocolNegotiator.java
+++ b/alts/src/main/java/io/grpc/alts/internal/AltsProtocolNegotiator.java
@@ -20,7 +20,9 @@ import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Preconditions;
 import com.google.protobuf.Any;
 import io.grpc.Attributes;
+import io.grpc.CallCredentials;
 import io.grpc.Grpc;
+import io.grpc.SecurityLevel;
 import io.grpc.Status;
 import io.grpc.alts.internal.RpcProtocolVersionsUtil.RpcVersionsCheckResult;
 import io.grpc.alts.internal.TsiHandshakeHandler.TsiHandshakeCompletionEvent;
@@ -122,6 +124,7 @@ public abstract class AltsProtocolNegotiator implements ProtocolNegotiator {
                     .set(TSI_PEER_KEY, altsEvt.peer())
                     .set(ALTS_CONTEXT_KEY, altsContext)
                     .set(Grpc.TRANSPORT_ATTR_REMOTE_ADDR, ctx.channel().remoteAddress())
+                    .set(CallCredentials.ATTR_SECURITY_LEVEL, SecurityLevel.PRIVACY_AND_INTEGRITY)
                     .build(),
                 new Security(new OtherSecurity("alts", Any.pack(altsContext.context))));
           }
diff --git a/alts/src/test/java/io/grpc/alts/internal/AltsProtocolNegotiatorTest.java b/alts/src/test/java/io/grpc/alts/internal/AltsProtocolNegotiatorTest.java
index 9114964cad..8ff2abc620 100644
--- a/alts/src/test/java/io/grpc/alts/internal/AltsProtocolNegotiatorTest.java
+++ b/alts/src/test/java/io/grpc/alts/internal/AltsProtocolNegotiatorTest.java
@@ -24,7 +24,9 @@ import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertTrue;
 
 import io.grpc.Attributes;
+import io.grpc.CallCredentials;
 import io.grpc.Grpc;
+import io.grpc.SecurityLevel;
 import io.grpc.alts.internal.Handshaker.HandshakerResult;
 import io.grpc.alts.internal.TsiFrameProtector.Consumer;
 import io.grpc.alts.internal.TsiPeer.Property;
@@ -343,6 +345,8 @@ public class AltsProtocolNegotiatorTest {
         .isEqualTo(mockedAltsContext);
     assertThat(grpcHandler.attrs.get(Grpc.TRANSPORT_ATTR_REMOTE_ADDR).toString())
         .isEqualTo("embedded");
+    assertThat(grpcHandler.attrs.get(CallCredentials.ATTR_SECURITY_LEVEL))
+        .isEqualTo(SecurityLevel.PRIVACY_AND_INTEGRITY);
   }
 
   private void doHandshake() throws Exception {