diff --git a/consensus/posv/posv.go b/consensus/posv/posv.go
index 09ad9ef02518..10d0b5201616 100644
--- a/consensus/posv/posv.go
+++ b/consensus/posv/posv.go
@@ -478,7 +478,7 @@ func (c *Posv) YourTurn(chain consensus.ChainReader, parent *types.Header, signe
 	masternodes := c.GetMasternodes(chain, parent)
 	snap, err := c.GetSnapshot(chain, parent)
 	if err != nil {
-		log.Error("Failed when trying to commit new work", "err", err)
+		log.Warn("Failed when trying to commit new work", "err", err)
 		return 0, -1, -1, false, err
 	}
 	if len(masternodes) == 0 {
@@ -499,7 +499,7 @@ func (c *Posv) YourTurn(chain consensus.ChainReader, parent *types.Header, signe
 		log.Info("Masternodes cycle info", "number of masternodes", len(masternodes), "previous", pre, "position", preIndex, "current", signer, "position", curIndex)
 	}
 	for i, s := range masternodes {
-		fmt.Printf("%d - %s\n", i, s.String())
+		log.Info("%d - %s\n", i, s.String())
 	}
 	if (preIndex+1)%len(masternodes) == curIndex {
 		return len(masternodes), preIndex, curIndex, true, nil
diff --git a/contracts/utils.go b/contracts/utils.go
index 8046d0603f71..05e10740d70b 100644
--- a/contracts/utils.go
+++ b/contracts/utils.go
@@ -85,7 +85,7 @@ func CreateTransactionSign(chainConfig *params.ChainConfig, pool *core.TxPool, m
 		// Add tx signed to local tx pool.
 		err = pool.AddLocal(txSigned)
 		if err != nil {
-			log.Error("Fail to add tx sign to local pool.", "error", err, "number", block.NumberU64(), "hash", block.Hash().Hex(), "from", account.Address, "nonce", nonce)
+			log.Warn("Fail to add tx sign to local pool.", "error", err, "number", block.NumberU64(), "hash", block.Hash().Hex(), "from", account.Address, "nonce", nonce)
 		}
 
 		// Create secret tx.
diff --git a/core/tx_pool.go b/core/tx_pool.go
index ec029ed93952..41f1a098878e 100644
--- a/core/tx_pool.go
+++ b/core/tx_pool.go
@@ -1171,7 +1171,7 @@ func (pool *TxPool) demoteUnexecutables() {
 		if list.Len() > 0 && list.txs.Get(nonce) == nil {
 			for _, tx := range list.Cap(0) {
 				hash := tx.Hash()
-				log.Error("Demoting invalidated transaction", "hash", hash)
+				log.Warn("Demoting invalidated transaction", "hash", hash)
 				pool.enqueueTx(hash, tx)
 			}
 		}
diff --git a/eth/downloader/downloader.go b/eth/downloader/downloader.go
index 4c285db2e6bc..6fbcc28a8316 100644
--- a/eth/downloader/downloader.go
+++ b/eth/downloader/downloader.go
@@ -295,7 +295,7 @@ func (d *Downloader) UnregisterPeer(id string) error {
 	logger := log.New("peer", id)
 	logger.Trace("Unregistering sync peer")
 	if err := d.peers.Unregister(id); err != nil {
-		logger.Error("Failed to unregister sync peer", "err", err)
+		logger.Warn("Failed to unregister sync peer", "err", err)
 		return err
 	}
 	d.queue.Revoke(id)
diff --git a/eth/handler.go b/eth/handler.go
index f1a408d53dab..322a888ade0d 100644
--- a/eth/handler.go
+++ b/eth/handler.go
@@ -205,7 +205,7 @@ func (pm *ProtocolManager) removePeer(id string) {
 	// Unregister the peer from the downloader and Ethereum peer set
 	pm.downloader.UnregisterPeer(id)
 	if err := pm.peers.Unregister(id); err != nil {
-		log.Error("Peer removal failed", "peer", id, "err", err)
+		log.Warn("Peer removal failed", "peer", id, "err", err)
 	}
 	// Hard disconnect at the networking layer
 	if peer != nil {
diff --git a/miner/worker.go b/miner/worker.go
index ffba0b1ca1b0..d229c7979d3a 100644
--- a/miner/worker.go
+++ b/miner/worker.go
@@ -499,7 +499,7 @@ func (self *worker) commitNewWork() {
 			c := self.engine.(*posv.Posv)
 			len, preIndex, curIndex, ok, err := c.YourTurn(self.chain, parent.Header(),self.coinbase)
 			if err != nil {
-				log.Error("Failed when trying to commit new work", "err", err)
+				log.Warn("Failed when trying to commit new work", "err", err)
 				return
 			}
 			if !ok {