diff --git a/src/query/src/optimizer/parallelize_scan.rs b/src/query/src/optimizer/parallelize_scan.rs
index eb712ec920..840cf16160 100644
--- a/src/query/src/optimizer/parallelize_scan.rs
+++ b/src/query/src/optimizer/parallelize_scan.rs
@@ -23,6 +23,7 @@ use datafusion::physical_plan::ExecutionPlan;
 use datafusion_common::tree_node::{Transformed, TreeNode};
 use datafusion_common::{DataFusionError, Result};
 use store_api::region_engine::PartitionRange;
+use store_api::storage::TimeSeriesDistribution;
 use table::table::scan::RegionScanExec;
 
 #[derive(Debug)]
@@ -61,13 +62,27 @@ impl ParallelizeScan {
                 } else if let Some(region_scan_exec) =
                     plan.as_any().downcast_ref::<RegionScanExec>()
                 {
+                    let expected_partition_num = config.execution.target_partitions;
                     if region_scan_exec.is_partition_set() {
                         return Ok(Transformed::no(plan));
                     }
 
+                    // don't parallelize if we want per series distribution
+                    if matches!(
+                        region_scan_exec.distribution(),
+                        Some(TimeSeriesDistribution::PerSeries)
+                    ) {
+                        let partition_range = region_scan_exec.get_partition_ranges();
+                        let mut new_partitions = vec![vec![]; expected_partition_num];
+                        new_partitions[0] = partition_range;
+                        let new_plan = region_scan_exec
+                            .with_new_partitions(new_partitions, expected_partition_num)
+                            .map_err(|e| DataFusionError::External(e.into_inner()))?;
+                        return Ok(Transformed::yes(Arc::new(new_plan)));
+                    }
+
                     let ranges = region_scan_exec.get_partition_ranges();
                     let total_range_num = ranges.len();
-                    let expected_partition_num = config.execution.target_partitions;
 
                     // assign ranges to each partition
                     let mut partition_ranges =