diff --git a/sdks/java/extensions/avro/build.gradle b/sdks/java/extensions/avro/build.gradle
index e3afb5ff52e4..6b24bf693dfb 100644
--- a/sdks/java/extensions/avro/build.gradle
+++ b/sdks/java/extensions/avro/build.gradle
@@ -40,6 +40,7 @@ def avroVersions = [
     '182' : "1.8.2",
     '192' : "1.9.2",
     '1102': "1.10.2",
+    '1120': "1.12.0",
 ]
 
 avroVersions.each { k, v ->
diff --git a/sdks/java/extensions/avro/src/test/java/org/apache/beam/sdk/extensions/avro/schemas/utils/AvroUtilsTest.java b/sdks/java/extensions/avro/src/test/java/org/apache/beam/sdk/extensions/avro/schemas/utils/AvroUtilsTest.java
index 57da8e77bb1b..282158bec03d 100644
--- a/sdks/java/extensions/avro/src/test/java/org/apache/beam/sdk/extensions/avro/schemas/utils/AvroUtilsTest.java
+++ b/sdks/java/extensions/avro/src/test/java/org/apache/beam/sdk/extensions/avro/schemas/utils/AvroUtilsTest.java
@@ -21,6 +21,7 @@
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
 
+import com.fasterxml.jackson.databind.ObjectMapper;
 import com.pholser.junit.quickcheck.From;
 import com.pholser.junit.quickcheck.Property;
 import com.pholser.junit.quickcheck.runner.JUnitQuickcheck;
@@ -284,10 +285,20 @@ public void avroToBeamRoundTrip(
     Iterable iterable = randomData(avroSchema, 10);
     List<GenericRecord> records = Lists.newArrayList((Iterable<GenericRecord>) iterable);
 
+    // AVRO-4139: GenericRecord.equals() throws "Can't compare maps!" for records with
+    // nested map types on Avro 1.12.0. Fall back to JSON tree comparison on that version
+    // only; keep direct equals for other versions.
+    boolean useJsonCompare = "1.12.0".equals(VERSION_AVRO);
+    ObjectMapper mapper = useJsonCompare ? new ObjectMapper() : null;
+
     for (GenericRecord record : records) {
       Row row = AvroUtils.toBeamRowStrict(record, schema);
       GenericRecord out = AvroUtils.toGenericRecord(row, avroSchema);
-      assertEquals(record, out);
+      if (useJsonCompare) {
+        assertEquals(mapper.readTree(record.toString()), mapper.readTree(out.toString()));
+      } else {
+        assertEquals(record, out);
+      }
     }
   }