diff --git a/sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/parquet/ParquetSchemaConverter.scala b/sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/parquet/ParquetSchemaConverter.scala
index 9e6f4447ca79..554e4e945b9a 100644
--- a/sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/parquet/ParquetSchemaConverter.scala
+++ b/sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/parquet/ParquetSchemaConverter.scala
@@ -309,10 +309,13 @@ class ParquetToSparkSchemaConverter(
             } else {
               TimestampNTZType
             }
-          // SPARK-40819: NANOS are not supported as a Timestamp, convert to LongType without
-          // timezone awareness to address behaviour regression introduced by SPARK-34661
+          // SPARK-40819 & SPARK-44988: NANOS are not supported as a Timestamp, convert to LongType
+          // The nanosAsLong config was originally intended as a migration flag, but since Spark
+          // doesn't have full NANOS support and real-world files exist with TIMESTAMP(NANOS,*)
+          // we always convert to LongType regardless of the config to prevent unreadable files.
+          // This handles both TIMESTAMP(NANOS,true) and TIMESTAMP(NANOS,false)
           case timestamp: TimestampLogicalTypeAnnotation
-            if timestamp.getUnit == TimeUnit.NANOS && nanosAsLong =>
+            if timestamp.getUnit == TimeUnit.NANOS =>
             LongType
           case time: TimeLogicalTypeAnnotation
             if time.getUnit == TimeUnit.MICROS && !time.isAdjustedToUTC =>
diff --git a/sql/core/src/test/scala/org/apache/spark/sql/execution/datasources/parquet/ParquetSchemaSuite.scala b/sql/core/src/test/scala/org/apache/spark/sql/execution/datasources/parquet/ParquetSchemaSuite.scala
index 56076175d60e..197461003d33 100644
--- a/sql/core/src/test/scala/org/apache/spark/sql/execution/datasources/parquet/ParquetSchemaSuite.scala
+++ b/sql/core/src/test/scala/org/apache/spark/sql/execution/datasources/parquet/ParquetSchemaSuite.scala
@@ -1109,15 +1109,15 @@ class ParquetSchemaSuite extends ParquetSchemaTest {
     }
   }
 
-  test("SPARK-40819: parquet file with TIMESTAMP(NANOS, true) (with default nanosAsLong=false)") {
+  test("SPARK-40819 & SPARK-44988: parquet file with TIMESTAMP(NANOS, true) " +
+    "(with default nanosAsLong=false)") {
+    // After SPARK-44988, TIMESTAMP(NANOS,*) is always converted to LongType regardless of
+    // nanosAsLong config to ensure files are readable
+    val tsAttribute = "birthday"
     val testDataPath = testFile("test-data/timestamp-nanos.parquet")
-    checkError(
-      exception = intercept[AnalysisException] {
-        spark.read.parquet(testDataPath).collect()
-      },
-      condition = "PARQUET_TYPE_ILLEGAL",
-      parameters = Map("parquetType" -> "INT64 (TIMESTAMP(NANOS,true))")
-    )
+    val data = spark.read.parquet(testDataPath).select(tsAttribute)
+    assert(data.schema.fields.head.dataType == LongType)
+    assert(data.orderBy(desc(tsAttribute)).take(1).head.getAs[Long](0) == 1668537129123534758L)
   }
 
   test("SPARK-47261: parquet file with unsupported type") {