diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/parser/AstBuilder.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/parser/AstBuilder.scala
index a43d28b045d0..23fe2268fbb5 100644
--- a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/parser/AstBuilder.scala
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/parser/AstBuilder.scala
@@ -482,7 +482,11 @@ class AstBuilder extends SqlBaseBaseVisitor[AnyRef] with SQLConfHelper with Logg
     // Before calling `toMap`, we check duplicated keys to avoid silently ignore partition values
     // in partition spec like PARTITION(a='1', b='2', a='3'). The real semantical check for
     // partition columns will be done in analyzer.
-    checkDuplicateKeys(parts.toSeq, ctx)
+    if (conf.caseSensitiveAnalysis) {
+      checkDuplicateKeys(parts.toSeq, ctx)
+    } else {
+      checkDuplicateKeys(parts.map(kv => kv._1.toLowerCase(Locale.ROOT) -> kv._2).toSeq, ctx)
+    }
     parts.toMap
   }
 
diff --git a/sql/core/src/test/scala/org/apache/spark/sql/SQLInsertTestSuite.scala b/sql/core/src/test/scala/org/apache/spark/sql/SQLInsertTestSuite.scala
index c7446c7a9f44..67c5f12dc71d 100644
--- a/sql/core/src/test/scala/org/apache/spark/sql/SQLInsertTestSuite.scala
+++ b/sql/core/src/test/scala/org/apache/spark/sql/SQLInsertTestSuite.scala
@@ -208,6 +208,28 @@ trait SQLInsertTestSuite extends QueryTest with SQLTestUtils {
       checkAnswer(spark.table("t"), Row("1", null))
     }
   }
+
+  test("SPARK-34556: " +
+    "checking duplicate static partition columns should respect case sensitive conf") {
+    withTable("t") {
+      sql(s"CREATE TABLE t(i STRING, c string) USING PARQUET PARTITIONED BY (c)")
+      val e = intercept[AnalysisException] {
+        sql("INSERT OVERWRITE t PARTITION (c='2', C='3') VALUES (1)")
+      }
+      assert(e.getMessage.contains("Found duplicate keys 'c'"))
+    }
+    // The following code is skipped for Hive because columns stored in Hive Metastore is always
+    // case insensitive and we cannot create such table in Hive Metastore.
+    if (!format.startsWith("hive")) {
+      withSQLConf(SQLConf.CASE_SENSITIVE.key -> "true") {
+        withTable("t") {
+          sql(s"CREATE TABLE t(i int, c string, C string) USING PARQUET PARTITIONED BY (c, C)")
+          sql("INSERT OVERWRITE t PARTITION (c='2', C='3') VALUES (1)")
+          checkAnswer(spark.table("t"), Row(1, "2", "3"))
+        }
+      }
+    }
+  }
 }
 
 class FileSourceSQLInsertTestSuite extends SQLInsertTestSuite with SharedSparkSession {