diff --git a/stringutils.go b/stringutils.go
index 741bb53..356b707 100644
--- a/stringutils.go
+++ b/stringutils.go
@@ -17,7 +17,6 @@ limitations under the License.
 package goutils
 
 import (
-	"bytes"
 	"fmt"
 	"strings"
 	"unicode"
@@ -107,23 +106,14 @@ Returns:
     the string without whitespaces
 */
 func DeleteWhiteSpace(str string) string {
-	if str == "" {
-		return str
-	}
-	sz := len(str)
-	var chs bytes.Buffer
-	count := 0
-	for i := 0; i < sz; i++ {
-		ch := rune(str[i])
+	var b strings.Builder
+	b.Grow(len(str))
+	for _, ch := range str {
 		if !unicode.IsSpace(ch) {
-			chs.WriteRune(ch)
-			count++
+			b.WriteRune(ch)
 		}
 	}
-	if count == sz {
-		return str
-	}
-	return chs.String()
+	return b.String()
 }
 
 /*
diff --git a/stringutils_test.go b/stringutils_test.go
index 76ef753..6ae991c 100644
--- a/stringutils_test.go
+++ b/stringutils_test.go
@@ -148,6 +148,14 @@ func TestDeleteWhiteSpace(t *testing.T) {
 	if x := DeleteWhiteSpace(str); x != out {
 		t.Errorf("IndexOf(%v) = %v, want %v", str, x, out)
 	}
+
+	// Test 3
+	str = " 测试 测试 测试 "
+	out = "测试测试测试"
+
+	if x := DeleteWhiteSpace(str); x != out {
+		t.Errorf("IndexOf(%v) = %v, want %v", str, x, out)
+	}
 }
 
 func TestIndexOfDifference(t *testing.T) {