diff --git a/.changeset/good-boats-fetch.md b/.changeset/good-boats-fetch.md
new file mode 100644
index 0000000..50426f8
--- /dev/null
+++ b/.changeset/good-boats-fetch.md
@@ -0,0 +1,5 @@
+---
+'@yourssu/utils': minor
+---
+
+change isEmail to return boolean value
diff --git a/packages/utils/src/isEmail.ts b/packages/utils/src/isEmail.ts
index 3859bb7..f699ddd 100644
--- a/packages/utils/src/isEmail.ts
+++ b/packages/utils/src/isEmail.ts
@@ -1,19 +1,13 @@
-export const isEmail = (email: string, domain?: string) => {
-  const regFull =
-    /^(([^<>()[\]\\.,;:\s@"]+(\.[^<>()[\]\\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;
-  if (regFull.test(String(email).toLowerCase())) {
-    return email;
+export const isEmail = (email: string, domain?: string): boolean => {
+  if (!domain) {
+    const regFull =
+      /^(([^<>()[\]\\.,;:\s@"]+(\.[^<>()[\]\\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;
+
+    return regFull.test(String(email).toLowerCase());
   }
 
-  const regHalf = /^(([^<>()[\]\\.,;:\s@"]+(\.[^<>()[\]\\.,;:\s@"]+)*)|(".+"))$/;
+  const regHalf = /^(([^<>()[\]\\.,;:\s@"]+(\[^<>()[\]\\.,;:\s@"]+)*)|(".+"))$/;
   const refDomain =
     /^@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;
-
-  if (domain) {
-    if (regHalf.test(String(email).toLowerCase()) && refDomain.test(String(domain).toLowerCase())) {
-      return email + domain;
-    }
-  }
-
-  throw new Error('given value is not valid');
+  return regHalf.test(String(email).toLowerCase()) && refDomain.test(String(domain).toLowerCase());
 };