diff --git a/workflow-engine-core/src/main/java/cn/axzo/workflow/core/version/MultiVersionBeanUtils.java b/workflow-engine-core/src/main/java/cn/axzo/workflow/core/version/MultiVersionBeanUtils.java
index 294de8973..a6393917d 100644
--- a/workflow-engine-core/src/main/java/cn/axzo/workflow/core/version/MultiVersionBeanUtils.java
+++ b/workflow-engine-core/src/main/java/cn/axzo/workflow/core/version/MultiVersionBeanUtils.java
@@ -28,7 +28,7 @@ public class MultiVersionBeanUtils {
             throw new NullPointerException("no beans of type " + clazz.getName());
         }
         if (StringUtils.isEmpty(version)) {
-            T t = beans.values().stream().filter(bean -> bean.getVersion() == null).findFirst().orElse(null);
+            T t = beans.values().stream().filter(bean -> bean.getVersion() == null || bean.getVersion() == UNKNOWN_VERSION).findFirst().orElse(null);
             if (t != null) {
                 return t;
             }
@@ -42,7 +42,8 @@ public class MultiVersionBeanUtils {
         }).collect(Collectors.toList());
         DefaultArtifactVersion targetVersion = new DefaultArtifactVersion(version);
         for (int i = sortedList.size() - 1; i >= 0; i--) {
-            int flag = sortedList.get(i).getVersion().compareTo(targetVersion);
+            DefaultArtifactVersion classVersion = sortedList.get(i).getVersion() == null ? UNKNOWN_VERSION : sortedList.get(i).getVersion();
+            int flag = classVersion.compareTo(targetVersion);
             if (flag <= 0) {
                 return sortedList.get(i);
             }