diff --git a/hutool-poi/src/main/java/cn/hutool/poi/excel/ExcelFileUtil.java b/hutool-poi/src/main/java/cn/hutool/poi/excel/ExcelFileUtil.java
index 3fd52b9e0..ec0140e03 100644
--- a/hutool-poi/src/main/java/cn/hutool/poi/excel/ExcelFileUtil.java
+++ b/hutool-poi/src/main/java/cn/hutool/poi/excel/ExcelFileUtil.java
@@ -1,7 +1,6 @@
 package cn.hutool.poi.excel;
 
 import cn.hutool.core.io.IORuntimeException;
-import cn.hutool.core.io.IoUtil;
 import org.apache.poi.poifs.filesystem.FileMagic;
 
 import java.io.File;
@@ -10,50 +9,35 @@ import java.io.InputStream;
 
 /**
  * Excel文件工具类
- * 
+ *
  * @author looly
  * @since 4.2.1
  */
 public class ExcelFileUtil {
 	// ------------------------------------------------------------------------------------------------ isXls
+
 	/**
 	 * 是否为XLS格式的Excel文件（HSSF）<br>
-	 * XLS文件主要用于Excel 97~2003创建
-	 * 
+	 * XLS文件主要用于Excel 97~2003创建<br>
+	 * 此方法会自动调用{@link InputStream#reset()}方法
+	 *
 	 * @param in excel输入流
 	 * @return 是否为XLS格式的Excel文件（HSSF）
 	 */
 	public static boolean isXls(InputStream in) {
-		/*
-		 * {@link java.io.PushbackInputStream}
-		 * PushbackInputStream的markSupported()为false，并不支持mark和reset
-		 * 如果强转成PushbackInputStream在调用FileMagic.valueOf(inputStream)时会报错
-		 * {@link FileMagic}
-		 * 报错内容：getFileMagic() only operates on streams which support mark(int)
-		 * 此处修改成 final InputStream inputStream = FileMagic.prepareToCheckMagic(in)
-		 * @author kefan.qu
-		 */
-		final InputStream inputStream = FileMagic.prepareToCheckMagic(in);
-		try {
-			return FileMagic.valueOf(inputStream) == FileMagic.OLE2;
-		} catch (IOException e) {
-			throw new IORuntimeException(e);
-		}
+		return FileMagic.OLE2 == getFileMagic(in);
 	}
 
 	/**
 	 * 是否为XLSX格式的Excel文件（XSSF）<br>
-	 * XLSX文件主要用于Excel 2007+创建
-	 * 
+	 * XLSX文件主要用于Excel 2007+创建<br>
+	 * 此方法会自动调用{@link InputStream#reset()}方法
+	 *
 	 * @param in excel输入流
 	 * @return 是否为XLSX格式的Excel文件（XSSF）
 	 */
 	public static boolean isXlsx(InputStream in) {
-		try {
-			return FileMagic.valueOf(IoUtil.toMarkSupportStream(in)) == FileMagic.OOXML;
-		} catch (IOException e) {
-			throw new IORuntimeException(e);
-		}
+		return FileMagic.OOXML == getFileMagic(in);
 	}
 
 	/**
@@ -71,4 +55,27 @@ public class ExcelFileUtil {
 			throw new IORuntimeException(e);
 		}
 	}
+
+	/**
+	 * {@link java.io.PushbackInputStream}
+	 * PushbackInputStream的markSupported()为false，并不支持mark和reset
+	 * 如果强转成PushbackInputStream在调用FileMagic.valueOf(inputStream)时会报错
+	 * {@link FileMagic}
+	 * 报错内容：getFileMagic() only operates on streams which support mark(int)
+	 * 此处修改成 final InputStream inputStream = FileMagic.prepareToCheckMagic(in)
+	 *
+	 * @param in {@link InputStream}
+	 * @author kefan.qu
+	 */
+	private static FileMagic getFileMagic(InputStream in) {
+		FileMagic magic;
+		final InputStream inputStream = FileMagic.prepareToCheckMagic(in);
+		try {
+			magic = FileMagic.valueOf(inputStream);
+		} catch (IOException e) {
+			throw new IORuntimeException(e);
+		}
+
+		return magic;
+	}
 }
diff --git a/hutool-poi/src/test/java/cn/hutool/poi/excel/ExcelFileUtilTest.java b/hutool-poi/src/test/java/cn/hutool/poi/excel/ExcelFileUtilTest.java
new file mode 100755
index 000000000..eae8aa284
--- /dev/null
+++ b/hutool-poi/src/test/java/cn/hutool/poi/excel/ExcelFileUtilTest.java
@@ -0,0 +1,33 @@
+package cn.hutool.poi.excel;
+
+import cn.hutool.core.io.FileUtil;
+import cn.hutool.core.io.IoUtil;
+import org.junit.Assert;
+import org.junit.Test;
+
+import java.io.InputStream;
+
+public class ExcelFileUtilTest {
+
+	@Test
+	public void xlsTest(){
+		InputStream in = FileUtil.getInputStream("aaa.xls");
+		try{
+			Assert.assertTrue(ExcelFileUtil.isXls(in));
+			Assert.assertFalse(ExcelFileUtil.isXlsx(in));
+		} finally {
+			IoUtil.close(in);
+		}
+	}
+
+	@Test
+	public void xlsxTest(){
+		InputStream in = FileUtil.getInputStream("aaa.xlsx");
+		try{
+			Assert.assertFalse(ExcelFileUtil.isXls(in));
+			Assert.assertTrue(ExcelFileUtil.isXlsx(in));
+		} finally {
+			IoUtil.close(in);
+		}
+	}
+}