diff --git a/test/signature-unit-tests.spec.ts b/test/signature-unit-tests.spec.ts
index 133fe92..c52680d 100644
--- a/test/signature-unit-tests.spec.ts
+++ b/test/signature-unit-tests.spec.ts
@@ -1275,4 +1275,23 @@ describe("Signature unit tests", function () {
     sig.signatureAlgorithm = "http://www.w3.org/2000/09/xmldsig#rsa-sha1";
     expect(() => sig.computeSignature(xml)).to.not.throw();
   });
+
+  it("throws when privateKeyPassword is wrong", function () {
+    const xml = "<root><x /></root>";
+    const sig = new SignedXml();
+    sig.privateKey = fs.readFileSync("./test/static/client_encrypted.pem");
+    sig.privateKeyPassword = "wrong password";
+    sig.canonicalizationAlgorithm = "http://www.w3.org/2001/10/xml-exc-c14n#";
+    sig.signatureAlgorithm = "http://www.w3.org/2000/09/xmldsig#rsa-sha1";
+    expect(() => sig.computeSignature(xml)).to.throw();
+  });
+
+  it("throws when privateKeyPassword is not set and private key is encrypted", function () {
+    const xml = "<root><x /></root>";
+    const sig = new SignedXml();
+    sig.privateKey = fs.readFileSync("./test/static/client_encrypted.pem");
+    sig.canonicalizationAlgorithm = "http://www.w3.org/2001/10/xml-exc-c14n#";
+    sig.signatureAlgorithm = "http://www.w3.org/2000/09/xmldsig#rsa-sha1";
+    expect(() => sig.computeSignature(xml)).to.throw();
+  });
 });