diff --git a/snail-job-client/snail-job-client-job-core/src/main/java/com/aizuda/snailjob/client/job/core/cache/ThreadPoolCache.java b/snail-job-client/snail-job-client-job-core/src/main/java/com/aizuda/snailjob/client/job/core/cache/ThreadPoolCache.java
index ac6a265c..a2d17a26 100644
--- a/snail-job-client/snail-job-client-job-core/src/main/java/com/aizuda/snailjob/client/job/core/cache/ThreadPoolCache.java
+++ b/snail-job-client/snail-job-client-job-core/src/main/java/com/aizuda/snailjob/client/job/core/cache/ThreadPoolCache.java
@@ -25,20 +25,20 @@ public class ThreadPoolCache {
     public static ThreadPoolExecutor createThreadPool(Long taskBatchId, int parallelNum) {
         if (CACHE_THREAD_POOL.containsKey(taskBatchId)) {
             ThreadPoolExecutor cacheThreadPool = CACHE_THREAD_POOL.get(taskBatchId);
-            if (cacheThreadPool.getCorePoolSize() == parallelNum) {
+            // 大于1说明已经更新了线程池的线程数，为了防止后面任务执行过程任务并行度改变影响已经产生的批次，这里不再做更新操作
+            if (cacheThreadPool.getCorePoolSize() > 1) {
                 return cacheThreadPool;
             }
 
             // 若能执行到这里只有分片任务(静态分片、MAP、MapReduce)才会需要多线程支持
-            cacheThreadPool.setCorePoolSize(parallelNum);
-            cacheThreadPool.setMaximumPoolSize(parallelNum);
+            cacheThreadPool.setCorePoolSize(Math.min(parallelNum, cacheThreadPool.getMaximumPoolSize()));
             return cacheThreadPool;
         }
 
         Supplier<ThreadPoolExecutor> supplier = () -> {
             ThreadPoolExecutor threadPoolExecutor = new ThreadPoolExecutor(
                     // 默认情况先只设置一个线程, 只有分片任务(静态分片、MAP、MapReduce)才会需要多线程支持
-                    1, 1, 10, TimeUnit.SECONDS, new LinkedBlockingQueue<>(),
+                    1, parallelNum, 10, TimeUnit.SECONDS, new LinkedBlockingQueue<>(),
                     new CustomizableThreadFactory(MessageFormat.format("snail-job-job-{0}-", taskBatchId)));
             threadPoolExecutor.allowCoreThreadTimeOut(true);
             return threadPoolExecutor;
diff --git a/snail-job-client/snail-job-client-job-core/src/main/java/com/aizuda/snailjob/client/job/core/executor/AbstractJobExecutor.java b/snail-job-client/snail-job-client-job-core/src/main/java/com/aizuda/snailjob/client/job/core/executor/AbstractJobExecutor.java
index 35b80057..f57f1b7f 100644
--- a/snail-job-client/snail-job-client-job-core/src/main/java/com/aizuda/snailjob/client/job/core/executor/AbstractJobExecutor.java
+++ b/snail-job-client/snail-job-client-job-core/src/main/java/com/aizuda/snailjob/client/job/core/executor/AbstractJobExecutor.java
@@ -26,6 +26,7 @@ import lombok.extern.slf4j.Slf4j;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
+import java.util.Optional;
 import java.util.concurrent.ThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
 
@@ -43,7 +44,8 @@ public abstract class AbstractJobExecutor implements IJobExecutor {
     public void jobExecute(JobContext jobContext) {
 
         // 创建可执行的任务
-        ThreadPoolExecutor threadPool = ThreadPoolCache.createThreadPool(jobContext.getTaskBatchId(), jobContext.getParallelNum());
+        Integer parallelNum = Optional.ofNullable(jobContext.getParallelNum()).orElse(1);
+        ThreadPoolExecutor threadPool = ThreadPoolCache.createThreadPool(jobContext.getTaskBatchId(), Math.max(1, parallelNum));
         ListeningExecutorService decorator = MoreExecutors.listeningDecorator(threadPool);
 
         // 将任务添加到时间轮中，到期停止任务