diff --git a/connector/connect/common/src/test/resources/query-tests/explain-results/function_base64.explain b/connector/connect/common/src/test/resources/query-tests/explain-results/function_base64.explain
index 99d842189c65..3b4e69469c30 100644
--- a/connector/connect/common/src/test/resources/query-tests/explain-results/function_base64.explain
+++ b/connector/connect/common/src/test/resources/query-tests/explain-results/function_base64.explain
@@ -1,2 +1,2 @@
-Project [staticinvoke(class org.apache.spark.sql.catalyst.expressions.Base64, StringType, encode, cast(g#0 as binary), false, BinaryType, BooleanType, true, true, true) AS base64(g)#0]
+Project [staticinvoke(class org.apache.spark.sql.catalyst.expressions.Base64, StringType, encode, cast(g#0 as binary), true, BinaryType, BooleanType, true, true, true) AS base64(g)#0]
 +- LocalRelation <empty>, [id#0L, a#0, b#0, d#0, e#0, f#0, g#0]
diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/internal/SQLConf.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/internal/SQLConf.scala
index 55f80645228d..44c58cd13ea8 100644
--- a/sql/catalyst/src/main/scala/org/apache/spark/sql/internal/SQLConf.scala
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/internal/SQLConf.scala
@@ -3229,14 +3229,13 @@ object SQLConf {
     .booleanConf
     .createWithDefault(false)
 
-  val CHUNK_BASE64_STRING_ENABLED = buildConf("spark.sql.legacy.chunkBase64String.enabled")
-    .internal()
+  val CHUNK_BASE64_STRING_ENABLED = buildConf("spark.sql.chunkBase64String.enabled")
     .doc("Whether to truncate string generated by the `Base64` function. When true, base64" +
       " strings generated by the base64 function are chunked into lines of at most 76" +
       " characters. When false, the base64 strings are not chunked.")
     .version("3.5.2")
     .booleanConf
-    .createWithDefault(false)
+    .createWithDefault(true)
 
   val ENABLE_DEFAULT_COLUMNS =
     buildConf("spark.sql.defaultColumn.enabled")
diff --git a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/expressions/StringExpressionsSuite.scala b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/expressions/StringExpressionsSuite.scala
index 75224bf33f53..c17268838368 100644
--- a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/expressions/StringExpressionsSuite.scala
+++ b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/expressions/StringExpressionsSuite.scala
@@ -517,6 +517,10 @@ class StringExpressionsSuite extends SparkFunSuite with ExpressionEvalHelper {
     withSQLConf(SQLConf.CHUNK_BASE64_STRING_ENABLED.key -> "true") {
       checkEvaluation(Base64(Literal(longString.getBytes)), chunkEncoded)
     }
+
+    // check if unbase64 works well for chunked and non-chunked encoded strings
+    checkEvaluation(StringDecode(UnBase64(Literal(encoded)), Literal("utf-8")), longString)
+    checkEvaluation(StringDecode(UnBase64(Literal(chunkEncoded)), Literal("utf-8")), longString)
   }
 
   test("initcap unit test") {