diff --git a/substratevm/src/com.oracle.svm.test/src/com/oracle/svm/test/jfr/AbstractJfrTest.java b/substratevm/src/com.oracle.svm.test/src/com/oracle/svm/test/jfr/AbstractJfrTest.java
index ffde76ad560..73b95ece753 100644
--- a/substratevm/src/com.oracle.svm.test/src/com/oracle/svm/test/jfr/AbstractJfrTest.java
+++ b/substratevm/src/com.oracle.svm.test/src/com/oracle/svm/test/jfr/AbstractJfrTest.java
@@ -41,6 +41,7 @@
 
 import org.graalvm.nativeimage.ImageInfo;
 import org.graalvm.nativeimage.hosted.Feature;
+import org.graalvm.nativeimage.hosted.RuntimeProxyCreation;
 import org.junit.After;
 import org.junit.Assert;
 import org.junit.BeforeClass;
@@ -54,6 +55,7 @@
 import jdk.jfr.Configuration;
 import jdk.jfr.consumer.RecordedEvent;
 import jdk.jfr.consumer.RecordingFile;
+import jdk.jfr.Unsigned;
 
 /** Base class for JFR unit tests. */
 public abstract class AbstractJfrTest {
@@ -196,4 +198,16 @@ public void afterRegistration(AfterRegistrationAccess access) {
          */
         ModuleSupport.accessPackagesToClass(ModuleSupport.Access.OPEN, JfrTestFeature.class, false, "jdk.internal.vm.compiler", "org.graalvm.compiler.serviceprovider");
     }
+
+    @Override
+    public void beforeAnalysis(BeforeAnalysisAccess access) {
+        /*
+         * Register proxies for event data assertion
+         *
+         * Unsigned added to be able to query RecordedObject.getLong() method, and this method
+         * checks if the value returned has the jdk.jfr.Unsigned. The jfr layer in HotSpot creates a
+         * proxy to query this information.
+         */
+        RuntimeProxyCreation.register(Unsigned.class);
+    }
 }