diff --git a/domain/miningmanager/mempool/error.go b/domain/miningmanager/mempool/error.go
index d698217d7..827fa9014 100644
--- a/domain/miningmanager/mempool/error.go
+++ b/domain/miningmanager/mempool/error.go
@@ -51,6 +51,7 @@ const (
 	RejectDifficulty      RejectCode = 0x44
 	RejectImmatureSpend   RejectCode = 0x45
 	RejectBadOrphan       RejectCode = 0x64
+	RejectSpamTx          RejectCode = 0x65
 )
 
 // Map of reject codes back strings for pretty printing.
diff --git a/domain/miningmanager/mempool/validate_and_insert_transaction.go b/domain/miningmanager/mempool/validate_and_insert_transaction.go
index d06a19cea..831557e13 100644
--- a/domain/miningmanager/mempool/validate_and_insert_transaction.go
+++ b/domain/miningmanager/mempool/validate_and_insert_transaction.go
@@ -2,6 +2,7 @@ package mempool
 
 import (
 	"fmt"
+	"github.com/kaspanet/kaspad/domain/consensus/utils/constants"
 
 	"github.com/kaspanet/kaspad/infrastructure/logger"
 
@@ -29,6 +30,12 @@ func (mp *mempool) validateAndInsertTransaction(transaction *externalapi.DomainT
 		return nil, err
 	}
 
+	numExtraOuts := len(transaction.Outputs) - len(transaction.Inputs)
+	if numExtraOuts > 2 && transaction.Fee < uint64(numExtraOuts)*constants.SompiPerKaspa {
+		log.Warnf("Rejected spam tx %s from mempool", consensushashing.TransactionID(transaction))
+		return nil, transactionRuleError(RejectSpamTx, fmt.Sprintf("Rejected spam tx %s from mempool", consensushashing.TransactionID(transaction)))
+	}
+
 	if len(missingOutpoints) > 0 {
 		if !allowOrphan {
 			str := fmt.Sprintf("Transaction %s is an orphan, where allowOrphan = false",