diff --git a/fe/src/main/java/org/apache/doris/rewrite/FEFunctions.java b/fe/src/main/java/org/apache/doris/rewrite/FEFunctions.java
index 6b572cc8dfd930..74a1607ae02125 100644
--- a/fe/src/main/java/org/apache/doris/rewrite/FEFunctions.java
+++ b/fe/src/main/java/org/apache/doris/rewrite/FEFunctions.java
@@ -38,6 +38,7 @@
 import org.joda.time.format.DateTimeFormatter;
 import org.joda.time.format.DateTimeFormatterBuilder;
 
+import java.text.SimpleDateFormat;
 import java.util.Calendar;
 import java.util.Date;
 import java.util.Locale;
@@ -55,9 +56,15 @@ public class FEFunctions {
 
     @FEFunction(name = "datediff", argTypes = { "DATETIME", "DATETIME" }, returnType = "INT")
     public static IntLiteral dateDiff(LiteralExpr first, LiteralExpr second) throws AnalysisException {
-        long diff = getTime(first) - getTime(second);
-        long datediff = diff / 1000 / 60 / 60 / 24;
-        return new IntLiteral(datediff, Type.INT);
+        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
+        try {
+            // DATEDIFF function only uses the date part for calculations and ignores the time part
+            long diff = sdf.parse(first.getStringValue()).getTime() - sdf.parse(second.getStringValue()).getTime();
+            long datediff = diff / 1000 / 60 / 60 / 24;
+            return new IntLiteral(datediff, Type.INT);
+        } catch (ParseException e) {
+            throw new AnalysisException(e.getLocalizedMessage());
+        }
     }
 
     @FEFunction(name = "date_add", argTypes = { "DATETIME", "INT" }, returnType = "DATETIME")
diff --git a/fe/src/test/java/org/apache/doris/rewrite/FEFunctionsTest.java b/fe/src/test/java/org/apache/doris/rewrite/FEFunctionsTest.java
index c2602077bd82b3..d09e35d32b9445 100644
--- a/fe/src/test/java/org/apache/doris/rewrite/FEFunctionsTest.java
+++ b/fe/src/test/java/org/apache/doris/rewrite/FEFunctionsTest.java
@@ -52,6 +52,17 @@ public void unixtimestampTest() {
         }
     }
 
+    @Test
+    public void dateDiffTest() throws AnalysisException {
+        IntLiteral actualResult = FEFunctions.dateDiff(new DateLiteral("2010-11-30 23:59:59", Type.DATETIME), new DateLiteral("2010-12-31", Type.DATE));
+        IntLiteral expectedResult = new IntLiteral(-31);
+        Assert.assertEquals(expectedResult, actualResult);
+
+        actualResult = FEFunctions.dateDiff(new DateLiteral("2010-11-30 23:59:50", Type.DATETIME), new DateLiteral("2010-12-30 23:59:59", Type.DATETIME));
+        expectedResult = new IntLiteral(-30);
+        Assert.assertEquals(expectedResult, actualResult);
+    }
+
     @Test
     public void dateAddTest() throws AnalysisException {
         DateLiteral actualResult = FEFunctions.dateAdd(new StringLiteral("2018-08-08"), new IntLiteral(1));