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 9250d0e23786ff7bf903b8c061aea244b1ffdf6d..5245c14a4c965f9286dc2181773d54d82ddf6d12 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
@@ -388,10 +388,11 @@ case class DataSource(
 
         val fileCatalog = if (sparkSession.sqlContext.conf.manageFilesourcePartitions &&
             catalogTable.isDefined && catalogTable.get.tracksPartitionsInCatalog) {
+          val defaultTableSize = sparkSession.sessionState.conf.defaultSizeInBytes
           new CatalogFileIndex(
             sparkSession,
             catalogTable.get,
-            catalogTable.get.stats.map(_.sizeInBytes.toLong).getOrElse(0L))
+            catalogTable.get.stats.map(_.sizeInBytes.toLong).getOrElse(defaultTableSize))
         } else {
           new InMemoryFileIndex(sparkSession, globbedPaths, options, Some(partitionSchema))
         }
diff --git a/sql/core/src/test/scala/org/apache/spark/sql/StatisticsCollectionSuite.scala b/sql/core/src/test/scala/org/apache/spark/sql/StatisticsCollectionSuite.scala
index 07408491953caa1d78cbaf1707b2dd3469c54afb..c663b31351b521d658f2ab694f0bdeccf01b6d7a 100644
--- a/sql/core/src/test/scala/org/apache/spark/sql/StatisticsCollectionSuite.scala
+++ b/sql/core/src/test/scala/org/apache/spark/sql/StatisticsCollectionSuite.scala
@@ -26,6 +26,7 @@ import scala.util.Random
 import org.apache.spark.sql.catalyst.TableIdentifier
 import org.apache.spark.sql.catalyst.plans.logical._
 import org.apache.spark.sql.execution.datasources.LogicalRelation
+import org.apache.spark.sql.internal.StaticSQLConf
 import org.apache.spark.sql.test.{SharedSQLContext, SQLTestUtils}
 import org.apache.spark.sql.test.SQLTestData.ArrayData
 import org.apache.spark.sql.types._
@@ -176,6 +177,7 @@ class StatisticsCollectionSuite extends StatisticsCollectionTestBase with Shared
  * when using the Hive external catalog) as well as in the sql/core module.
  */
 abstract class StatisticsCollectionTestBase extends QueryTest with SQLTestUtils {
+  import testImplicits._
 
   private val dec1 = new java.math.BigDecimal("1.000000000000000000")
   private val dec2 = new java.math.BigDecimal("8.000000000000000000")
@@ -242,4 +244,20 @@ abstract class StatisticsCollectionTestBase extends QueryTest with SQLTestUtils
       }
     }
   }
+
+  // This test will be run twice: with and without Hive support
+  test("SPARK-18856: non-empty partitioned table should not report zero size") {
+    withTable("ds_tbl", "hive_tbl") {
+      spark.range(100).select($"id", $"id" % 5 as "p").write.partitionBy("p").saveAsTable("ds_tbl")
+      val stats = spark.table("ds_tbl").queryExecution.optimizedPlan.statistics
+      assert(stats.sizeInBytes > 0, "non-empty partitioned table should not report zero size.")
+
+      if (spark.conf.get(StaticSQLConf.CATALOG_IMPLEMENTATION) == "hive") {
+        sql("CREATE TABLE hive_tbl(i int) PARTITIONED BY (j int)")
+        sql("INSERT INTO hive_tbl PARTITION(j=1) SELECT 1")
+        val stats2 = spark.table("hive_tbl").queryExecution.optimizedPlan.statistics
+        assert(stats2.sizeInBytes > 0, "non-empty partitioned table should not report zero size.")
+      }
+    }
+  }
 }