diff --git a/lib/passport-wsfed-saml2/samlp.js b/lib/passport-wsfed-saml2/samlp.js
index 3683b2c..8e32e75 100644
--- a/lib/passport-wsfed-saml2/samlp.js
+++ b/lib/passport-wsfed-saml2/samlp.js
@@ -383,6 +383,17 @@ Samlp.prototype = {
     }
     var responseXML = responseXMLs[0];
 
+    // Check Issuer if options.idpIssuer is set.
+    if (self.options.idpIssuer) {
+      const issuer = xpath.select("//*[local-name(.)='Issuer']", samlResponse);
+      if (issuer.length === 0) {
+          return callback(new Error(`No SAML issuer found.`));
+      }
+      if (issuer[0].textContent !== self.options.idpIssuer) {
+          return callback(new Error(`Unknown SAML issuer. Expected ${self.options.idpIssuer}. Received: ${issuer[0].textContent}`));
+      }
+    }
+
     self.isValidResponseID(responseXML.getAttribute('ID'), function(err){
       if (err && self.options.checkResponseID) { return callback(err); }
 
diff --git a/test/samlp.tests.js b/test/samlp.tests.js
index 302a14a..0377a16 100644
--- a/test/samlp.tests.js
+++ b/test/samlp.tests.js
@@ -135,6 +135,7 @@ describe('samlp (unit tests)', function () {
     var samlpResponseWithStatusNotMappedStatus = '<samlp:Response xmlns:samlp="urn:oasis:names:tc:SAML:2.0:protocol" ID="id" InResponseTo="response" Version="2.0" IssueInstant="2014-02-25T15:20:20Z" Destination="https://auth0-dev-ed.my.salesforce.com"><saml:Issuer xmlns:saml="urn:oasis:names:tc:SAML:2.0:assertion">urn:fixture-test</saml:Issuer><samlp:Status><samlp:StatusCode Value="urn:oasis:names:tc:SAML:2.0:status:Success"/></samlp:Status></samlp:Response>';
     var xmlWithNoSamlResponse = '<myxml>somedata</myxml>';
     var xmlWithSeveralSamlResponseElements = '<samlp:Response xmlns:samlp="urn:oasis:names:tc:SAML:2.0:protocol" ID="id" InResponseTo="response" Version="2.0" IssueInstant="2014-02-25T15:20:20Z" Destination="https://auth0-dev-ed.my.salesforce.com"><saml:Issuer xmlns:saml="urn:oasis:names:tc:SAML:2.0:assertion">urn:fixture-test</saml:Issuer><samlp:Status><samlp:StatusCode Value="urn:oasis:names:tc:SAML:2.0:status:Responder"/></samlp:Status><samlp:Response xmlns:samlp="urn:oasis:names:tc:SAML:2.0:protocol" ID="id" InResponseTo="response" Version="2.0" IssueInstant="2014-02-25T15:20:20Z" Destination="https://auth0-dev-ed.my.salesforce.com"><saml:Issuer xmlns:saml="urn:oasis:names:tc:SAML:2.0:assertion">urn:fixture-test</saml:Issuer><samlp:Status><samlp:StatusCode Value="urn:oasis:names:tc:SAML:2.0:status:Responder"/></samlp:Status></samlp:Response></samlp:Response>';
+    var samlpResponseWithNoIssuer = '<samlp:Response xmlns:samlp="urn:oasis:names:tc:SAML:2.0:protocol" ID="id" InResponseTo="response" Version="2.0" IssueInstant="2014-02-25T15:20:20Z" Destination="https://auth0-dev-ed.my.salesforce.com"><samlp:Status><samlp:StatusCode Value="urn:oasis:names:tc:SAML:2.0:status:Responder"/></samlp:Status></samlp:Response>';
 
     it('should return error for AuthnFailed status with generic message', function(done){
       var samlp = new Samlp({ checkDestination: false });
@@ -309,6 +310,26 @@ describe('samlp (unit tests)', function () {
       });
     });
 
+    it('should return error for empty Issuer', function(done){
+      var samlp = new Samlp({ idpIssuer: 'urn:fixture-test' });
+      samlp.validateSamlResponse(samlpResponseWithNoIssuer, function (err) {
+        expect(err).to.be.ok;
+        expect(err.name).to.equals('Error');
+        expect(err.message).to.equal('No SAML issuer found.');
+        done();
+      });
+    });
+
+    it('should return error if IdP Issuer is different', function(done){
+      var samlp = new Samlp({ checkDestination: false, idpIssuer: 'url:fixture-test-invalid' });
+      samlp.validateSamlResponse(samlpResponseWithStatusNotMappedStatus, function (err) {
+        expect(err).to.be.ok;
+        expect(err.name).to.equals('Error');
+        expect(err.message).to.equal('Unknown SAML issuer. Expected url:fixture-test-invalid. Received: urn:fixture-test');
+        done();
+      });
+    });
+
     it('should return profile even if the namespace is in response element', function(done){
        var cert = fs.readFileSync(__dirname + '/test-auth0.cer');
        var encodedSamlResponse = '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';
@@ -377,6 +398,7 @@ describe('samlp (unit tests)', function () {
         checkExpiration: false,
         checkDestination: false,
         checkRecipient: false,
+        idpIssuer: 'https://oam-stg.putnam.com/oam/fed',
         realm: 'urn:auth0:fireglass:putnam'
       };
       var samlp = new Samlp(options, new Saml(options));
@@ -396,6 +418,7 @@ describe('samlp (unit tests)', function () {
         checkExpiration: false,
         checkDestination: false,
         checkRecipient: false,
+        idpIssuer: 'http://localhost:8080/simplesaml/saml2/idp/metadata.php',
         realm: 'urn:auth0:login0:simplephp'
       };
       var samlp = new Samlp(options, new Saml(options));