diff --git a/src/main/java/com/alibaba/druid/sql/dialect/mysql/parser/MySqlExprParser.java b/src/main/java/com/alibaba/druid/sql/dialect/mysql/parser/MySqlExprParser.java
index 6902f82f14..2e7825a89e 100644
--- a/src/main/java/com/alibaba/druid/sql/dialect/mysql/parser/MySqlExprParser.java
+++ b/src/main/java/com/alibaba/druid/sql/dialect/mysql/parser/MySqlExprParser.java
@@ -415,7 +415,7 @@ public class MySqlExprParser extends SQLExprParser {
 
             MySqlIntervalExpr intervalExpr = new MySqlIntervalExpr();
             intervalExpr.setValue(value);
-            intervalExpr.setUnit(MySqlIntervalUnit.valueOf(unit));
+            intervalExpr.setUnit(MySqlIntervalUnit.valueOf(unit.toUpperCase()));
 
             return intervalExpr;
         }