diff --git a/src/models/StratumV1Client.ts b/src/models/StratumV1Client.ts
index b43880f..fa83cfd 100644
--- a/src/models/StratumV1Client.ts
+++ b/src/models/StratumV1Client.ts
@@ -54,6 +54,8 @@ export class StratumV1Client {
 
     private buffer: string = '';
 
+    private miningSubmissionHashes = new Set<string>()
+
     constructor(
         public readonly socket: Socket,
         private readonly stratumV1JobsService: StratumV1JobsService,
@@ -368,6 +370,9 @@ export class StratumV1Client {
 
         this.stratumSubscription = this.stratumV1JobsService.newMiningJob$.subscribe(async (jobTemplate) => {
             try {
+                if(jobTemplate.blockData.clearJobs){
+                    this.miningSubmissionHashes.clear();
+                }
                 await this.sendNewMiningJob(jobTemplate);
             } catch (e) {
                 await this.socket.end();
@@ -466,6 +471,21 @@ export class StratumV1Client {
             }
         }
 
+        const submissionHash = submission.hash();
+        if(this.miningSubmissionHashes.has(submissionHash)){
+            const err = new StratumErrorMessage(
+                submission.id,
+                eStratumErrorCode.DuplicateShare,
+                'Duplicate share').response();
+            console.error(err);
+            const success = await this.write(err);
+            if (!success) {
+                return false;
+            }
+            return false;
+        }else{
+            this.miningSubmissionHashes.add(submissionHash);
+        }
 
         const job = this.stratumV1JobsService.getJobById(submission.jobId);
 
@@ -529,16 +549,6 @@ export class StratumV1Client {
 
             } catch (e) {
                 console.log(e);
-                const err = new StratumErrorMessage(
-                    submission.id,
-                    eStratumErrorCode.DuplicateShare,
-                    'Duplicate share').response();
-                console.error(err);
-                const success = await this.write(err);
-                if (!success) {
-                    return false;
-                }
-                return false;
             }
 
             if (submissionDifficulty > this.entity.bestDifficulty) {
diff --git a/src/models/stratum-messages/MiningSubmitMessage.ts b/src/models/stratum-messages/MiningSubmitMessage.ts
index 127689c..9c5f00a 100644
--- a/src/models/stratum-messages/MiningSubmitMessage.ts
+++ b/src/models/stratum-messages/MiningSubmitMessage.ts
@@ -3,6 +3,8 @@ import { ArrayMaxSize, ArrayMinSize, IsArray, IsString } from 'class-validator';
 
 import { eRequestMethod } from '../enums/eRequestMethod';
 import { StratumBaseMessage } from './StratumBaseMessage';
+import * as bitcoinjs from 'bitcoinjs-lib';
+
 
 export class MiningSubmitMessage extends StratumBaseMessage {
 
@@ -63,6 +65,11 @@ export class MiningSubmitMessage extends StratumBaseMessage {
         };
     }
 
+    public hash(): string{
+        const buffer = Buffer.from(this.versionMask + this.nonce + this.extraNonce2 + this.ntime + this.jobId);
+        return bitcoinjs.crypto.hash256(buffer).toString('base64');
+    }
+