diff --git a/common/unsafe/src/main/java/org/apache/spark/unsafe/types/UTF8String.java b/common/unsafe/src/main/java/org/apache/spark/unsafe/types/UTF8String.java
index 50a3cc6049ea..2657bc3e885c 100644
--- a/common/unsafe/src/main/java/org/apache/spark/unsafe/types/UTF8String.java
+++ b/common/unsafe/src/main/java/org/apache/spark/unsafe/types/UTF8String.java
@@ -1192,7 +1192,7 @@ public UTF8String repeat(int times) {
    * @return the position of the first occurrence of the empty substr (now, always 0)
    */
   public int indexOfEmpty(int start) {
-    return 0; // TODO: Fix this behaviour (SPARK-48284)
+    return start >= numChars() ? 0 : start;
   }
 
   /**
diff --git a/common/unsafe/src/test/java/org/apache/spark/unsafe/types/UTF8StringSuite.java b/common/unsafe/src/test/java/org/apache/spark/unsafe/types/UTF8StringSuite.java
index c4a66fdffdd4..feb31ec50728 100644
--- a/common/unsafe/src/test/java/org/apache/spark/unsafe/types/UTF8StringSuite.java
+++ b/common/unsafe/src/test/java/org/apache/spark/unsafe/types/UTF8StringSuite.java
@@ -271,6 +271,8 @@ public void indexOf() {
     assertEquals(0, EMPTY_UTF8.indexOf(EMPTY_UTF8, 0));
     assertEquals(-1, EMPTY_UTF8.indexOf(fromString("l"), 0));
     assertEquals(0, fromString("hello").indexOf(EMPTY_UTF8, 0));
+    assertEquals(2, fromString("hello").indexOf(EMPTY_UTF8, 2));
+    assertEquals(0, fromString("hello").indexOf(EMPTY_UTF8, 9));
     assertEquals(2, fromString("hello").indexOf(fromString("l"), 0));
     assertEquals(3, fromString("hello").indexOf(fromString("l"), 3));
     assertEquals(-1, fromString("hello").indexOf(fromString("a"), 0));