diff --git a/core/tx_pool.go b/core/tx_pool.go
index 552d3692b3..144046524f 100644
--- a/core/tx_pool.go
+++ b/core/tx_pool.go
@@ -105,7 +105,7 @@ var (
 type TxStatus uint
 
 const (
-	TxStatusUnknown TxStatus = iota
+	TxStatusUnknown  TxStatus = iota
 	TxStatusQueued
 	TxStatusPending
 	TxStatusIncluded
@@ -316,11 +316,11 @@ func (pool *TxPool) loop() {
 
 				pool.mu.Unlock()
 			}
-		// Be unsubscribed due to system stopped
+			// Be unsubscribed due to system stopped
 		case <-pool.chainHeadSub.Err():
 			return
 
-		// Handle stats reporting ticks
+			// Handle stats reporting ticks
 		case <-report.C:
 			pool.mu.RLock()
 			pending, queued := pool.stats()
@@ -332,7 +332,7 @@ func (pool *TxPool) loop() {
 				prevPending, prevQueued, prevStales = pending, queued, stales
 			}
 
-		// Handle inactive account transaction eviction
+			// Handle inactive account transaction eviction
 		case <-evict.C:
 			pool.mu.Lock()
 			for addr := range pool.queue {
@@ -349,7 +349,7 @@ func (pool *TxPool) loop() {
 			}
 			pool.mu.Unlock()
 
-		// Handle local transaction journal rotation
+			// Handle local transaction journal rotation
 		case <-journal.C:
 			if pool.journal != nil {
 				pool.mu.Lock()
@@ -606,7 +606,7 @@ func (pool *TxPool) validateTx(tx *types.Transaction, local bool) error {
 	}
 	// Drop non-local transactions under our own minimal accepted gas price
 	local = local || pool.locals.contains(from) // account may be local even if the transaction arrived from the network
-	if !local && pool.gasPrice.Cmp(tx.GasPrice()) > 0 {
+	if !local && pool.gasPrice.Cmp(tx.GasPrice()) > 0 || tx.GasPrice().Cmp(big.NewInt(0)) < 1 {
 		return ErrUnderpriced
 	}
 	// Ensure the transaction adheres to nonce ordering