diff --git a/hutool-core/src/main/java/org/dromara/hutool/core/text/StrJoiner.java b/hutool-core/src/main/java/org/dromara/hutool/core/text/StrJoiner.java
index e6f0c121f..a686a5437 100644
--- a/hutool-core/src/main/java/org/dromara/hutool/core/text/StrJoiner.java
+++ b/hutool-core/src/main/java/org/dromara/hutool/core/text/StrJoiner.java
@@ -379,7 +379,7 @@ public class StrJoiner implements Appendable, Serializable {
 	 * @since 5.7.22
 	 */
 	public int length() {
-		return (this.appendable != null ? this.appendable.toString().length() + suffix.length() :
+		return (this.appendable != null ? this.appendable.toString().length() + StrUtil.length(suffix) :
 				null == this.emptyResult ? -1 : emptyResult.length());
 	}
 
diff --git a/hutool-core/src/test/java/org/dromara/hutool/core/text/StrJoinerTest.java b/hutool-core/src/test/java/org/dromara/hutool/core/text/StrJoinerTest.java
index 343c5c7ef..d1c26f693 100644
--- a/hutool-core/src/test/java/org/dromara/hutool/core/text/StrJoinerTest.java
+++ b/hutool-core/src/test/java/org/dromara/hutool/core/text/StrJoinerTest.java
@@ -111,4 +111,13 @@ public class StrJoinerTest {
 		final StrJoiner merge = joiner1.merge(joiner2);
 		Assertions.assertEquals("[123,456,789]", merge.toString());
 	}
+
+	@Test
+	void issue3444Test() {
+		final StrJoiner strJoinerEmpty = StrJoiner.of(",");
+		Assertions.assertEquals(0, strJoinerEmpty.length());
+
+		final StrJoiner strJoinerWithContent = StrJoiner.of(",").append("haha");
+		Assertions.assertEquals(4, strJoinerWithContent.length());
+	}
 }