diff --git a/chain/service/src/chain_service.rs b/chain/service/src/chain_service.rs
index bb16d37ce0..422a70130e 100644
--- a/chain/service/src/chain_service.rs
+++ b/chain/service/src/chain_service.rs
@@ -1,7 +1,7 @@
 // Copyright (c) The Starcoin Core Contributors
 // SPDX-License-Identifier: Apache-2.0
 
-use anyhow::{bail, format_err, Error, Result};
+use anyhow::{format_err, Error, Result};
 use starcoin_chain::BlockChain;
 use starcoin_chain_api::message::{ChainRequest, ChainResponse};
 use starcoin_chain_api::{
@@ -455,13 +455,11 @@ impl ReadableChainService for ChainReaderServiceInner {
     }
 
     fn get_dag_state(&self) -> Result<DagStateView> {
-        if self.main.check_chain_type()? != ChainType::Dag {
-            bail!("The dag block is not built yet.");
-        }
         let state = self.main.get_dag_state()?;
+        let pruning_point = self.main.status().head().pruning_point();
         Ok(DagStateView {
             tips: state.tips,
-            pruning_point: state.pruning_point,
+            pruning_point,
         })
     }
 
diff --git a/chain/src/chain.rs b/chain/src/chain.rs
index 8e133e0c03..d326000b6d 100644
--- a/chain/src/chain.rs
+++ b/chain/src/chain.rs
@@ -2052,10 +2052,7 @@ impl BlockChain {
         if self.epoch.end_block_number() == block.header().number() {
             self.epoch = get_epoch_from_statedb(&self.statedb)?;
         }
-        self.dag.save_dag_state(DagState {
-            tips,
-            pruning_point: block.header().pruning_point(),
-        })?;
+        self.dag.save_dag_state(DagState { tips })?;
         Ok(executed_block)
     }
 }
diff --git a/flexidag/src/blockdag.rs b/flexidag/src/blockdag.rs
index bb8a02d49c..730c38e3c9 100644
--- a/flexidag/src/blockdag.rs
+++ b/flexidag/src/blockdag.rs
@@ -115,7 +115,6 @@ impl BlockDAG {
         self.commit(genesis, origin)?;
         self.save_dag_state(DagState {
             tips: vec![genesis_id],
-            pruning_point: genesis_id,
         })?;
         Ok(origin)
     }
@@ -337,13 +336,9 @@ impl BlockDAG {
         block_header: &BlockHeader,
         genesis_id: HashValue,
     ) -> anyhow::Result<()> {
-        let dag_state = DagState {
-            tips: block_header.parents(),
-            pruning_point: block_header.pruning_point(),
-        };
         let ghostdata = self.ghost_dag_manager().ghostdag(&block_header.parents())?;
         let next_pruning_point = self.pruning_point_manager().next_pruning_point(
-            &dag_state,
+            block_header.pruning_point(),
             &ghostdata,
             pruning_depth,
             pruning_finality,
@@ -388,24 +383,36 @@ impl BlockDAG {
             info,
             storage.get_accumulator_store(AccumulatorStoreType::Block),
         );
-        match self.storage.state_store.read().get_state_by_hash(
+
+        let read_guard = self.storage.state_store.read();
+
+        let update_dag_state = match read_guard.get_state_by_hash(
             accumulator
                 .get_leaf(0)?
                 .ok_or_else(|| format_err!("no leaf when upgrading dag db"))?,
         ) {
-            anyhow::Result::Ok(dag_state) => match self.storage.state_store.read().get_state() {
+            anyhow::Result::Ok(dag_state) => match read_guard.get_state() {
                 anyhow::Result::Ok(saved_dag_state) => {
                     info!("The dag state is {:?}", saved_dag_state);
+                    None
                 }
-                Err(_) => {
-                    info!("The dag state will be saved as {:?}", dag_state);
-                    self.storage.state_store.write().insert(dag_state)?;
-                }
+                Err(_) => Some(dag_state),
             },
             Err(_) => {
-                warn!("Cannot get the dag state by genesis id. Might be it is a new node. The dag state will be: {:?}", self.storage.state_store.read().get_state()?);
+                warn!("Cannot get the dag state by genesis id. Might be it is a new node. The dag state will be: {:?}", read_guard.get_state()?);
+                None
             }
+        };
+
+        drop(read_guard);
+
+        if let Some(dag_state) = update_dag_state {
+            let write_guard = self.storage.state_store.write();
+            info!("The dag state will be saved as {:?}", dag_state);
+            write_guard.insert(dag_state)?;
+            drop(write_guard);
         }
+
         anyhow::Ok(())
     }
 }
diff --git a/flexidag/src/consensusdb/consenses_state.rs b/flexidag/src/consensusdb/consenses_state.rs
index a6b0f3cf09..481c415fdb 100644
--- a/flexidag/src/consensusdb/consenses_state.rs
+++ b/flexidag/src/consensusdb/consenses_state.rs
@@ -9,7 +9,6 @@ use std::sync::Arc;
 #[derive(Eq, PartialEq, Hash, Deserialize, Serialize, Clone, Debug, Default)]
 pub struct DagState {
     pub tips: Vec<Hash>,
-    pub pruning_point: Hash,
 }
 
 pub(crate) const DAG_STATE_STORE_CF: &str = "dag-state-store";
@@ -88,9 +87,6 @@ pub struct DagStateView {
 
 impl DagStateView {
     pub fn into_state(self) -> DagState {
-        DagState {
-            tips: self.tips,
-            pruning_point: self.pruning_point,
-        }
+        DagState { tips: self.tips }
     }
 }
diff --git a/flexidag/src/prune/pruning_point_manager.rs b/flexidag/src/prune/pruning_point_manager.rs
index 4af1a2b404..b7496e456a 100644
--- a/flexidag/src/prune/pruning_point_manager.rs
+++ b/flexidag/src/prune/pruning_point_manager.rs
@@ -40,9 +40,10 @@ impl<T: ReachabilityStoreReader + Clone> PruningPointManagerT<T> {
     pub fn prune(
         &self,
         dag_state: &DagState,
+        current_pruning_point: HashValue,
         next_pruning_point: HashValue,
     ) -> anyhow::Result<Vec<HashValue>> {
-        if dag_state.pruning_point == HashValue::zero() {
+        if current_pruning_point == HashValue::zero() {
             return Ok(dag_state.tips.clone());
         }
         anyhow::Ok(
@@ -60,12 +61,12 @@ impl<T: ReachabilityStoreReader + Clone> PruningPointManagerT<T> {
 
     pub(crate) fn next_pruning_point(
         &self,
-        dag_state: &DagState,
+        pruning_point: HashValue,
         ghostdata: &GhostdagData,
         pruning_depth: u64,
         pruning_finality: u64,
     ) -> anyhow::Result<HashValue> {
-        let pruning_ghostdata = self.ghost_dag_store.get_data(dag_state.pruning_point)?;
+        let pruning_ghostdata = self.ghost_dag_store.get_data(pruning_point)?;
         let min_required_blue_score_for_next_pruning_point =
             (self.finality_score(pruning_ghostdata.blue_score, pruning_finality) + 1)
                 * pruning_finality;
@@ -74,12 +75,10 @@ impl<T: ReachabilityStoreReader + Clone> PruningPointManagerT<T> {
             "min_required_blue_score_for_next_pruning_point: {:?}",
             min_required_blue_score_for_next_pruning_point
         );
-        let mut latest_pruning_ghost_data = self
-            .ghost_dag_store
-            .get_compact_data(dag_state.pruning_point)?;
+        let mut latest_pruning_ghost_data = self.ghost_dag_store.get_compact_data(pruning_point)?;
         if min_required_blue_score_for_next_pruning_point + pruning_depth <= ghostdata.blue_score {
             for child in self.reachability_service().forward_chain_iterator(
-                dag_state.pruning_point,
+                pruning_point,
                 ghostdata.selected_parent,
                 true,
             ) {
@@ -106,7 +105,7 @@ impl<T: ReachabilityStoreReader + Clone> PruningPointManagerT<T> {
         }
 
         if latest_pruning_ghost_data.selected_parent == HashValue::new(ORIGIN) {
-            anyhow::Ok(dag_state.pruning_point) // still genesis
+            anyhow::Ok(pruning_point) // still genesis
         } else {
             anyhow::Ok(latest_pruning_ghost_data.selected_parent)
         }
diff --git a/flexidag/tests/tests.rs b/flexidag/tests/tests.rs
index df89f47fa5..6483bfe933 100644
--- a/flexidag/tests/tests.rs
+++ b/flexidag/tests/tests.rs
@@ -316,7 +316,6 @@ fn test_dag_tips_store() {
 
     let state = DagState {
         tips: vec![Hash::random()],
-        pruning_point: Hash::random(),
     };
     dag.storage
         .state_store
@@ -936,7 +935,6 @@ fn test_prune() -> anyhow::Result<()> {
     // prunning process begins
     dag.save_dag_state(DagState {
         tips: vec![block_red_3.id(), block_main_5.id()],
-        pruning_point: genesis.id(),
     })?;
 
     let MineNewDagBlockInfo {