diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/collectionOperations.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/collectionOperations.scala
index b34189504b3ca..bb2163c1e847f 100644
--- a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/collectionOperations.scala
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/expressions/collectionOperations.scala
@@ -2711,7 +2711,7 @@ object Sequence {
         val maxEstimatedArrayLength =
           getSequenceLength(startMicros, stopMicros, intervalStepInMicros)
 
-        val stepSign = if (stopMicros >= startMicros) +1 else -1
+        val stepSign = if (intervalStepInMicros > 0) +1 else -1
         val exclusiveItem = stopMicros + stepSign
         val arr = new Array[T](maxEstimatedArrayLength)
         var t = startMicros
@@ -2786,7 +2786,7 @@ object Sequence {
          |
          |  $sequenceLengthCode
          |
-         |  final int $stepSign = $stopMicros >= $startMicros ? +1 : -1;
+         |  final int $stepSign = $intervalInMicros > 0 ? +1 : -1;
          |  final long $exclusiveItem = $stopMicros + $stepSign;
          |
          |  $arr = new $elemType[$arrLength];
diff --git a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/expressions/CollectionExpressionsSuite.scala b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/expressions/CollectionExpressionsSuite.scala
index 095894b9fffac..d79f06f556f11 100644
--- a/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/expressions/CollectionExpressionsSuite.scala
+++ b/sql/catalyst/src/test/scala/org/apache/spark/sql/catalyst/expressions/CollectionExpressionsSuite.scala
@@ -1888,6 +1888,24 @@ class CollectionExpressionsSuite extends SparkFunSuite with ExpressionEvalHelper
       Seq(Date.valueOf("2018-01-01")))
   }
 
+  test("SPARK-36639: Start and end equal in month range with a negative step") {
+    checkEvaluation(new Sequence(
+      Literal(Date.valueOf("2018-01-01")),
+      Literal(Date.valueOf("2018-01-01")),
+      Literal(stringToInterval("interval -1 day"))),
+      Seq(Date.valueOf("2018-01-01")))
+    checkEvaluation(new Sequence(
+      Literal(Date.valueOf("2018-01-01")),
+      Literal(Date.valueOf("2018-01-01")),
+      Literal(stringToInterval("interval -1 month"))),
+      Seq(Date.valueOf("2018-01-01")))
+    checkEvaluation(new Sequence(
+      Literal(Date.valueOf("2018-01-01")),
+      Literal(Date.valueOf("2018-01-01")),
+      Literal(stringToInterval("interval -1 year"))),
+      Seq(Date.valueOf("2018-01-01")))
+  }
+
   test("SPARK-33386: element_at ArrayIndexOutOfBoundsException") {
     Seq(true, false).foreach { ansiEnabled =>
       withSQLConf(SQLConf.ANSI_ENABLED.key -> ansiEnabled.toString) {