diff --git a/src/mito2/src/memtable/time_partition.rs b/src/mito2/src/memtable/time_partition.rs
index d422daa0b2..fd7e0e1a17 100644
--- a/src/mito2/src/memtable/time_partition.rs
+++ b/src/mito2/src/memtable/time_partition.rs
@@ -656,6 +656,11 @@ impl TimePartitions {
 
         Ok(())
     }
+
+    /// Timeseries count in all time partitions.
+    pub(crate) fn series_count(&self) -> usize {
+        self.inner.lock().unwrap().series_count()
+    }
 }
 
 /// Computes the start timestamp of the partition for `ts`.
@@ -697,6 +702,13 @@ impl PartitionsInner {
         self.next_memtable_id += 1;
         id
     }
+
+    pub(crate) fn series_count(&self) -> usize {
+        self.parts
+            .iter()
+            .map(|p| p.memtable.stats().series_count)
+            .sum()
+    }
 }
 
 /// Time range of a partition.
diff --git a/src/mito2/src/region/opener.rs b/src/mito2/src/region/opener.rs
index 50e4537550..885963f21e 100644
--- a/src/mito2/src/region/opener.rs
+++ b/src/mito2/src/region/opener.rs
@@ -665,9 +665,10 @@ where
     // to avoid reading potentially incomplete entries in the future.
     (on_region_opened)(region_id, flushed_entry_id, provider).await?;
 
+    let series_count = version_control.current().series_count();
     info!(
-        "Replay WAL for region: {}, rows recovered: {}, last entry id: {}",
-        region_id, rows_replayed, last_entry_id
+        "Replay WAL for region: {}, rows recovered: {}, last entry id: {}, total timeseries replayed: {}",
+        region_id, rows_replayed, last_entry_id, series_count
     );
     Ok(last_entry_id)
 }
diff --git a/src/mito2/src/region/version.rs b/src/mito2/src/region/version.rs
index c1198e4d16..935b2bdc12 100644
--- a/src/mito2/src/region/version.rs
+++ b/src/mito2/src/region/version.rs
@@ -249,6 +249,13 @@ pub(crate) struct VersionControlData {
     pub(crate) is_dropped: bool,
 }
 
+impl VersionControlData {
+    /// Approximate timeseries count in current version.
+    pub(crate) fn series_count(&self) -> usize {
+        self.version.memtables.mutable.series_count()
+    }
+}
+
 /// Static metadata of a region.
 #[derive(Clone, Debug)]
 pub(crate) struct Version {