diff --git a/sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/DataSource.scala b/sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/DataSource.scala
index e9b8fae7cd735..3615afcf86c7a 100644
--- a/sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/DataSource.scala
+++ b/sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/DataSource.scala
@@ -343,7 +343,12 @@ case class DataSource(
         val baseRelation =
           dataSource.createRelation(sparkSession.sqlContext, caseInsensitiveOptions)
         if (baseRelation.schema != schema) {
-          throw new AnalysisException(s"$className does not allow user-specified schemas.")
+          throw new AnalysisException(
+            "The user-specified schema doesn't match the actual schema: " +
+            s"user-specified: ${schema.toDDL}, actual: ${baseRelation.schema.toDDL}. If " +
+            "you're using DataFrameReader.schema API or creating a table, please do not " +
+            "specify the schema. Or if you're scanning an existed table, please drop " +
+            "it and re-create it.")
         }
         baseRelation
 
diff --git a/sql/core/src/test/scala/org/apache/spark/sql/sources/TableScanSuite.scala b/sql/core/src/test/scala/org/apache/spark/sql/sources/TableScanSuite.scala
index d4e117953942e..9a95bf770772e 100644
--- a/sql/core/src/test/scala/org/apache/spark/sql/sources/TableScanSuite.scala
+++ b/sql/core/src/test/scala/org/apache/spark/sql/sources/TableScanSuite.scala
@@ -358,7 +358,7 @@ class TableScanSuite extends DataSourceTest with SharedSparkSession {
     // Make sure we do throw correct exception when users use a relation provider that
     // only implements the RelationProvider or the SchemaRelationProvider.
     Seq("TEMPORARY VIEW", "TABLE").foreach { tableType =>
-      val schemaNotAllowed = intercept[Exception] {
+      val schemaNotMatch = intercept[Exception] {
         sql(
           s"""
              |CREATE $tableType relationProvierWithSchema (i int)
@@ -369,7 +369,8 @@ class TableScanSuite extends DataSourceTest with SharedSparkSession {
              |)
            """.stripMargin)
       }
-      assert(schemaNotAllowed.getMessage.contains("does not allow user-specified schemas"))
+      assert(schemaNotMatch.getMessage.contains(
+        "The user-specified schema doesn't match the actual schema"))
 
       val schemaNeeded = intercept[Exception] {
         sql(
diff --git a/sql/core/src/test/scala/org/apache/spark/sql/test/DataFrameReaderWriterSuite.scala b/sql/core/src/test/scala/org/apache/spark/sql/test/DataFrameReaderWriterSuite.scala
index 55a60940a7750..fb939007697c2 100644
--- a/sql/core/src/test/scala/org/apache/spark/sql/test/DataFrameReaderWriterSuite.scala
+++ b/sql/core/src/test/scala/org/apache/spark/sql/test/DataFrameReaderWriterSuite.scala
@@ -489,11 +489,10 @@ class DataFrameReaderWriterSuite extends QueryTest with SharedSparkSession with
     // when users do not specify the schema
     checkAnswer(dfReader.load(), spark.range(1, 11).toDF())
 
-    // when users specify the schema
+    // when users specify a wrong schema
     val inputSchema = new StructType().add("s", IntegerType, nullable = false)
     val e = intercept[AnalysisException] { dfReader.schema(inputSchema).load() }
-    assert(e.getMessage.contains(
-      "org.apache.spark.sql.sources.SimpleScanSource does not allow user-specified schemas"))
+    assert(e.getMessage.contains("The user-specified schema doesn't match the actual schema"))
   }
 
   test("read a data source that does not extend RelationProvider") {