diff --git a/application/Espo/Core/Record/Access/LinkCheck.php b/application/Espo/Core/Record/Access/LinkCheck.php
index 671229a48c..84a64100eb 100644
--- a/application/Espo/Core/Record/Access/LinkCheck.php
+++ b/application/Espo/Core/Record/Access/LinkCheck.php
@@ -41,9 +41,11 @@ use Espo\Core\Utils\Metadata;
 use Espo\Entities\User;
 use Espo\Modules\Crm\Entities\Account;
 use Espo\Modules\Crm\Entities\Contact;
+use Espo\ORM\Defs;
 use Espo\ORM\Defs\RelationDefs;
 use Espo\ORM\Entity;
 use Espo\ORM\EntityManager;
+use Espo\ORM\Type\RelationType;
 
 /**
  * Check access for record linking.
@@ -57,6 +59,7 @@ class LinkCheck
      * @param string[] $noEditAccessRequiredLinkList
      */
     public function __construct(
+        private Defs $ormDefs,
         private EntityManager $entityManager,
         private Acl $acl,
         private Metadata $metadata,
@@ -234,6 +237,16 @@ class LinkCheck
         $this->linkEntityAccessCheck($entity, $foreignEntity, $link);
     }
 
+    /**
+     * Check unlink access for a specific foreign entity.
+     * @throws Forbidden
+     */
+    public function processUnlinkForeign(Entity $entity, string $link, Entity $foreignEntity): void
+    {
+        $this->processLinkForeign($entity, $link, $foreignEntity);
+        $this->processUnlinkForeignRequired($entity, $link, $foreignEntity);
+    }
+
     /**
      * @throws Forbidden
      */
@@ -369,4 +382,64 @@ class LinkCheck
 
         return $checker;
     }
+
+    /**
+     * @throws Forbidden
+     */
+    private function processUnlinkForeignRequired(Entity $entity, string $link, Entity $foreignEntity): void
+    {
+        $relationDefs = $this->ormDefs
+            ->getEntity($entity->getEntityType())
+            ->tryGetRelation($link);
+
+        if (!$relationDefs) {
+            return;
+        }
+
+        if (
+            !$relationDefs->hasForeignEntityType() ||
+            !$relationDefs->hasForeignRelationName()
+        ) {
+            return;
+        }
+
+        $foreignLink = $relationDefs->getForeignRelationName();
+
+        $foreignRelationDefs = $this->ormDefs
+            ->getEntity($foreignEntity->getEntityType())
+            ->tryGetRelation($foreignLink);
+
+        if (!$foreignRelationDefs) {
+            return;
+        }
+
+        if (
+            !in_array($foreignRelationDefs->getType(), [
+                RelationType::BELONGS_TO,
+                RelationType::HAS_ONE,
+                RelationType::BELONGS_TO_PARENT,
+            ])
+        ) {
+            return;
+        }
+
+        $foreignFieldDefs = $this->ormDefs
+            ->getEntity($foreignEntity->getEntityType())
+            ->tryGetField($foreignLink);
+
+        if (!$foreignFieldDefs) {
+            return;
+        }
+
+        if (!$foreignFieldDefs->getParam('required')) {
+            return;
+        }
+
+        throw ForbiddenSilent::createWithBody(
+            "Can't unlink required field ({$foreignEntity->getEntityType()}:$foreignLink}).",
+            ErrorBody::create()
+                ->withMessageTranslation('cannotUnrelateRequiredLink')
+                ->encode()
+        );
+    }
 }
diff --git a/application/Espo/Core/Record/Service.php b/application/Espo/Core/Record/Service.php
index 0d3ec66b4c..09cfcc9fd7 100644
--- a/application/Espo/Core/Record/Service.php
+++ b/application/Espo/Core/Record/Service.php
@@ -1158,7 +1158,7 @@ class Service implements Crud,
             throw new NotFound();
         }
 
-        $this->getLinkCheck()->processLinkForeign($entity, $link, $foreignEntity);
+        $this->getLinkCheck()->processUnlinkForeign($entity, $link, $foreignEntity);
 
         $this->recordHookManager->processBeforeUnlink($entity, $link, $foreignEntity);
 
diff --git a/application/Espo/Resources/i18n/en_US/Global.json b/application/Espo/Resources/i18n/en_US/Global.json
index 1de28c977a..8740d520a3 100644
--- a/application/Espo/Resources/i18n/en_US/Global.json
+++ b/application/Espo/Resources/i18n/en_US/Global.json
@@ -372,6 +372,7 @@
         "noAccessToRecord": "Operation requires `{action}` access to record.",
         "noAccessToForeignRecord": "Operation requires `{action}` access to foreign record.",
         "noLinkAccess": "No access to link operation for a specific record.",
+        "cannotUnrelateRequiredLink": "Can't unrelate required link.",
         "cannotRelateNonExisting": "Can't relate with non-existing {foreignEntityType} record.",
         "cannotRelateForbidden": "Can't relate with forbidden {foreignEntityType} record. `{action}` access required.",
         "cannotRelateForbiddenLink": "No access to link '{link}'.",
diff --git a/tests/integration/Espo/Record/LinkTest.php b/tests/integration/Espo/Record/LinkTest.php
new file mode 100644
index 0000000000..16db44d6d9
--- /dev/null
+++ b/tests/integration/Espo/Record/LinkTest.php
@@ -0,0 +1,75 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM - Open Source CRM application.
+ * Copyright (C) 2014-2023 Yurii Kuznietsov, Taras Machyshyn, Oleksii Avramenko
+ * Website: https://www.espocrm.com
+ *
+ * EspoCRM is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * EspoCRM is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace tests\integration\Espo\Record;
+
+use Espo\Core\Exceptions\Forbidden;
+use Espo\Core\Record\ServiceContainer;
+use Espo\Core\Utils\Metadata;
+use Espo\Modules\Crm\Entities\Account;
+use Espo\Modules\Crm\Entities\CaseObj;
+use Espo\ORM\EntityManager;
+use tests\integration\Core\BaseTestCase;
+
+class LinkTest extends BaseTestCase
+{
+    public function testUnlinkRequired1(): void
+    {
+        $metadata = $this->getContainer()->getByClass(Metadata::class);
+
+        $metadata->set('entityDefs', CaseObj::ENTITY_TYPE, [
+            'fields' => [
+                'account' => ['required' => true]
+            ]
+        ]);
+        $metadata->save();
+
+        $this->reCreateApplication();
+
+        $em = $this->getContainer()->getByClass(EntityManager::class);
+
+        $account = $em->createEntity(Account::ENTITY_TYPE, [
+            'name' => 'Test',
+        ]);
+
+        $case = $em->createEntity(CaseObj::ENTITY_TYPE, [
+            'name' => 'Test',
+            'accountId' => $account->getId(),
+        ]);
+
+        $accountService = $this->getContainer()
+            ->getByClass(ServiceContainer::class)
+            ->getByClass(Account::class);
+
+        $this->expectException(Forbidden::class);
+
+        /** @noinspection PhpUnhandledExceptionInspection */
+        $accountService->unlink($account->getId(), 'cases', $case->getId());
+    }
+}