diff --git a/src/main/java/org/apache/commons/validator/routines/EmailValidator.java b/src/main/java/org/apache/commons/validator/routines/EmailValidator.java
index 0eb58d1a9..460397456 100644
--- a/src/main/java/org/apache/commons/validator/routines/EmailValidator.java
+++ b/src/main/java/org/apache/commons/validator/routines/EmailValidator.java
@@ -42,7 +42,11 @@ public class EmailValidator implements Serializable {
     private static final String WORD = "((" + VALID_CHARS + "|')+|" + QUOTED_USER + ")";
 
     private static final String EMAIL_REGEX = "^(.+)@(\\S+)$";
-    private static final String IP_DOMAIN_REGEX = "^\\[(.*)\\]$";
+
+    /**
+     * RFC 5321 section 4.1.3: an IPv6 address literal carries the "IPv6:" tag (case-insensitive), an IPv4 literal is untagged.
+     */
+    private static final String IP_DOMAIN_REGEX = "^\\[((?i)IPv6:)?(.*)\\]$";
     private static final String USER_REGEX = "^" + WORD + "(\\." + WORD + ")*$";
 
     private static final Pattern EMAIL_PATTERN = Pattern.compile(EMAIL_REGEX);
@@ -195,9 +199,11 @@ protected boolean isValidDomain(final String domain) {
         final Matcher ipDomainMatcher = IP_DOMAIN_PATTERN.matcher(domain);
 
         if (ipDomainMatcher.matches()) {
-            final InetAddressValidator inetAddressValidator =
-                    InetAddressValidator.getInstance();
-            return inetAddressValidator.isValid(ipDomainMatcher.group(1));
+            final InetAddressValidator inetAddressValidator = InetAddressValidator.getInstance();
+            if (ipDomainMatcher.group(1) != null) {
+                return inetAddressValidator.isValidInet6Address(ipDomainMatcher.group(2));
+            }
+            return inetAddressValidator.isValidInet4Address(ipDomainMatcher.group(2));
         }
         // Domain is symbolic name
         if (allowTld) {
diff --git a/src/test/java/org/apache/commons/validator/routines/EmailValidatorTest.java b/src/test/java/org/apache/commons/validator/routines/EmailValidatorTest.java
index 87b3839a5..9ab3ddfd6 100644
--- a/src/test/java/org/apache/commons/validator/routines/EmailValidatorTest.java
+++ b/src/test/java/org/apache/commons/validator/routines/EmailValidatorTest.java
@@ -453,6 +453,23 @@ void testEmailWithNumericAddress() {
         assertTrue(validator.isValid("someone@yahoo.com"));
     }
 
+    /**
+     * Tests IPv6 address literals in the domain, which RFC 5321 section 4.1.3 tags with "IPv6:".
+     */
+    @Test
+    void testEmailWithIpv6AddressLiteral() {
+        // Tagged IPv6 literals are accepted; the tag is ABNF-literal text so it is case insensitive.
+        assertTrue(validator.isValid("someone@[IPv6:2001:db8::1]"));
+        assertTrue(validator.isValid("someone@[IPv6:::1]"));
+        assertTrue(validator.isValid("someone@[ipv6:fe80::1]"));
+        // A bare IPv6 literal without the tag is not a valid address literal.
+        assertFalse(validator.isValid("someone@[2001:db8::1]"));
+        assertFalse(validator.isValid("someone@[::1]"));
+        // The tag is IPv6 only; an IPv4 literal stays untagged.
+        assertTrue(validator.isValid("someone@[216.109.118.76]"));
+        assertFalse(validator.isValid("someone@[IPv6:216.109.118.76]"));
+    }
+
     /**
      * VALIDATOR-296 - A / or a ! is valid in the user part, but not in the domain part
      */