diff --git a/datafusion/physical-expr/src/window/nth_value.rs b/datafusion/physical-expr/src/window/nth_value.rs
index eed733c19b516..5c7c891f92d27 100644
--- a/datafusion/physical-expr/src/window/nth_value.rs
+++ b/datafusion/physical-expr/src/window/nth_value.rs
@@ -199,7 +199,8 @@ impl PartitionEvaluator for NthValueEvaluator {
                 }
             }
         };
-        if is_prunable {
+        // Do not memoize results when nulls are ignored.
+        if is_prunable && !self.ignore_nulls {
             if self.state.finalized_result.is_none() && !is_reverse_direction {
                 let result = ScalarValue::try_from_array(out, size - 1)?;
                 self.state.finalized_result = Some(result);
diff --git a/datafusion/sqllogictest/test_files/window.slt b/datafusion/sqllogictest/test_files/window.slt
index a95441cf233fd..f9ebccca6c63e 100644
--- a/datafusion/sqllogictest/test_files/window.slt
+++ b/datafusion/sqllogictest/test_files/window.slt
@@ -4486,15 +4486,15 @@ SELECT LAST_VALUE(column1) OVER(ORDER BY column2 DESC NULLS LAST), column2 FROM
 NULL 2
 NULL 1
 
-# query II
-# SELECT LAST_VALUE(column1) IGNORE NULLS OVER(ORDER BY column2 DESC NULLS LAST), column2 FROM t;
-# ----
-# 6 6
-# 5 5
-# 3 4
-# 4 3
-# 4 2
-# 4 1
+query II
+SELECT LAST_VALUE(column1) IGNORE NULLS OVER(ORDER BY column2 DESC NULLS LAST), column2 FROM t;
+----
+6 6
+5 5
+3 4
+4 3
+4 2
+4 1
 
 query II
 SELECT LAST_VALUE(column1) OVER(ORDER BY column2 DESC NULLS LAST ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING), column2 FROM t;