diff --git a/src/excel/poi/ExcelKit.java b/src/excel/poi/ExcelKit.java
index 430c3ac..bac3044 100644
--- a/src/excel/poi/ExcelKit.java
+++ b/src/excel/poi/ExcelKit.java
@@ -250,6 +250,7 @@ public class ExcelKit {
 			wk = new XSSFWorkbook(new FileInputStream(file));
 		}
 		Sheet sheet = sheetName == null ? wk.getSheetAt(0) : wk.getSheet(sheetName);
+		if (sheet == null) throw new OfficeXmlFileException("sheet["+sheetName+"] can't find");
 		return readExcel(sheet, fields, lastRowNum);
 	}