diff --git a/docs/documentation/assertions.md b/docs/documentation/assertions.md
index 35868f93..e683ab40 100644
--- a/docs/documentation/assertions.md
+++ b/docs/documentation/assertions.md
@@ -47,6 +47,9 @@ It asserts that the selected classes **do not depend** on the target classes.
 ## shouldNotConstruct()
 It asserts that the selected classes **do not use the constructor** of the target classes.
 
+## shouldNotExist()
+It asserts that the selected classes **should not exist**.
+
 ## shouldApplyAttribute()
 It asserts that the selected classes **apply** the target attributes.
 
diff --git a/src/Rule/Assertion/Declaration/ShouldNotExist/ShouldNotExist.php b/src/Rule/Assertion/Declaration/ShouldNotExist/ShouldNotExist.php
new file mode 100644
index 00000000..f1f5beab
--- /dev/null
+++ b/src/Rule/Assertion/Declaration/ShouldNotExist/ShouldNotExist.php
@@ -0,0 +1,61 @@
+<?php declare(strict_types=1);
+
+namespace PHPat\Rule\Assertion\Declaration\ShouldNotExist;
+
+use PHPat\Configuration;
+use PHPat\Rule\Assertion\Declaration\DeclarationAssertion;
+use PHPat\Rule\Assertion\Declaration\ValidationTrait;
+use PHPat\Statement\Builder\StatementBuilderFactory;
+use PhpParser\Node;
+use PHPStan\Analyser\Scope;
+use PHPStan\Node\InClassNode;
+use PHPStan\Reflection\ClassReflection;
+use PHPStan\Reflection\ReflectionProvider;
+use PHPStan\Rules\Rule;
+use PHPStan\Type\FileTypeMapper;
+
+/**
+ * @implements Rule<InClassNode>
+ */
+final class ShouldNotExist extends DeclarationAssertion implements Rule
+{
+    use ValidationTrait;
+
+    public function __construct(
+        StatementBuilderFactory $statementBuilderFactory,
+        Configuration $configuration,
+        ReflectionProvider $reflectionProvider,
+        FileTypeMapper $fileTypeMapper
+    ) {
+        parent::__construct(
+            __CLASS__,
+            $statementBuilderFactory,
+            $configuration,
+            $reflectionProvider,
+            $fileTypeMapper
+        );
+    }
+
+    public function getNodeType(): string
+    {
+        return InClassNode::class;
+    }
+
+    protected function applyValidation(string $ruleName, ClassReflection $subject, bool $meetsDeclaration, array $tips, array $params = []): array
+    {
+        return $this->applyShouldNot($ruleName, $subject, $meetsDeclaration, $tips, $params);
+    }
+
+    protected function getMessage(string $ruleName, string $subject, array $params = []): string
+    {
+        return $this->prepareMessage(
+            $ruleName,
+            sprintf('%s should not exist', $subject)
+        );
+    }
+
+    protected function meetsDeclaration(Node $node, Scope $scope, array $params = []): bool
+    {
+        return true;
+    }
+}
diff --git a/src/Test/Builder/AssertionStep.php b/src/Test/Builder/AssertionStep.php
index 1d04cbf0..b133202c 100644
--- a/src/Test/Builder/AssertionStep.php
+++ b/src/Test/Builder/AssertionStep.php
@@ -11,6 +11,7 @@
 use PHPat\Rule\Assertion\Declaration\ShouldNotBeAbstract\ShouldNotBeAbstract;
 use PHPat\Rule\Assertion\Declaration\ShouldNotBeFinal\ShouldNotBeFinal;
 use PHPat\Rule\Assertion\Declaration\ShouldNotBeReadonly\ShouldNotBeReadonly;
+use PHPat\Rule\Assertion\Declaration\ShouldNotExist\ShouldNotExist;
 use PHPat\Rule\Assertion\Relation\CanOnlyDepend\CanOnlyDepend;
 use PHPat\Rule\Assertion\Relation\ShouldApplyAttribute\ShouldApplyAttribute;
 use PHPat\Rule\Assertion\Relation\ShouldExtend\ShouldExtend;
@@ -157,4 +158,11 @@ public function shouldBeInterface(): TipOrBuildStep
 
         return new TipOrBuildStep($this->rule);
     }
+
+    public function shouldNotExist(): TipOrBuildStep
+    {
+        $this->rule->assertion = ShouldNotExist::class;
+
+        return new TipOrBuildStep($this->rule);
+    }
 }
diff --git a/tests/unit/rules/ShouldNotExist/ShouldNotExistTest.php b/tests/unit/rules/ShouldNotExist/ShouldNotExistTest.php
new file mode 100644
index 00000000..ed91639b
--- /dev/null
+++ b/tests/unit/rules/ShouldNotExist/ShouldNotExistTest.php
@@ -0,0 +1,48 @@
+<?php
+declare(strict_types=1);
+
+namespace Tests\PHPat\unit\rules\ShouldNotExist;
+
+use PHPat\Configuration;
+use PHPat\Rule\Assertion\Declaration\ShouldNotExist\ShouldNotExist;
+use PHPat\Selector\Classname;
+use PHPat\Statement\Builder\StatementBuilderFactory;
+use PHPStan\Rules\Rule;
+use PHPStan\Testing\RuleTestCase;
+use PHPStan\Type\FileTypeMapper;
+use Tests\PHPat\fixtures\FixtureClass;
+use Tests\PHPat\unit\FakeTestParser;
+
+/**
+ * @extends RuleTestCase<ShouldNotExist>
+ * @internal
+ * @coversNothing
+ */
+class ShouldNotExistTest extends RuleTestCase
+{
+    public const RULE_NAME = 'test_FixtureClassShouldNotExist';
+
+    public function testRule(): void
+    {
+        $this->analyse(['tests/fixtures/FixtureClass.php'], [
+            [sprintf('%s should not exist', FixtureClass::class), 29],
+        ]);
+    }
+
+    protected function getRule(): Rule
+    {
+        $testParser = FakeTestParser::create(
+            self::RULE_NAME,
+            ShouldNotExist::class,
+            [new Classname(FixtureClass::class, false)],
+            []
+        );
+
+        return new ShouldNotExist(
+            new StatementBuilderFactory($testParser),
+            new Configuration(false, true, false),
+            $this->createReflectionProvider(),
+            self::getContainer()->getByType(FileTypeMapper::class)
+        );
+    }
+}