diff --git a/sql/core/src/main/scala/org/apache/spark/sql/internal/SQLConf.scala b/sql/core/src/main/scala/org/apache/spark/sql/internal/SQLConf.scala
index 5e19984debaa710ed8bbaa1a9d0630330163b9c0..7933d12e284f17716806b4cf1ee043d33e513690 100644
--- a/sql/core/src/main/scala/org/apache/spark/sql/internal/SQLConf.scala
+++ b/sql/core/src/main/scala/org/apache/spark/sql/internal/SQLConf.scala
@@ -167,7 +167,9 @@ object SQLConf {
       .createWithDefault(true)
 
   val CASE_SENSITIVE = SQLConfigBuilder("spark.sql.caseSensitive")
-    .doc("Whether the query analyzer should be case sensitive or not. Default to case insensitive.")
+    .internal()
+    .doc("Whether the query analyzer should be case sensitive or not. " +
+      "Default to case insensitive. It is highly discouraged to turn on case sensitive mode.")
     .booleanConf
     .createWithDefault(false)