diff --git a/src/Illuminate/Database/Eloquent/Concerns/HasRelationships.php b/src/Illuminate/Database/Eloquent/Concerns/HasRelationships.php
index 92c3758e15f9..c48bd22a54f4 100644
--- a/src/Illuminate/Database/Eloquent/Concerns/HasRelationships.php
+++ b/src/Illuminate/Database/Eloquent/Concerns/HasRelationships.php
@@ -233,7 +233,7 @@ public function morphTo($name = null, $type = null, $id = null, $ownerKey = null
         // If the type value is null it is probably safe to assume we're eager loading
         // the relationship. In this case we'll just pass in a dummy query where we
         // need to remove any eager loads that may already be defined on a model.
-        return empty($class = $this->{$type})
+        return is_null($class = $this->{$type}) || $class === ''
                     ? $this->morphEagerTo($name, $type, $id, $ownerKey)
                     : $this->morphInstanceTo($class, $name, $type, $id, $ownerKey);
     }
diff --git a/tests/Database/DatabaseEloquentMorphToTest.php b/tests/Database/DatabaseEloquentMorphToTest.php
index 5f9049b4a4a5..c01dfd8b924f 100644
--- a/tests/Database/DatabaseEloquentMorphToTest.php
+++ b/tests/Database/DatabaseEloquentMorphToTest.php
@@ -90,6 +90,16 @@ public function testMorphToWithArrayDefault()
         $this->assertSame('taylor', $result->username);
     }
 
+    public function testMorphToWithZeroMorphType()
+    {
+        $parent = $this->getMockBuilder(EloquentMorphToModelStub::class)->setMethods(['getAttribute', 'morphEagerTo', 'morphInstanceTo'])->getMock();
+        $parent->method('getAttribute')->with('relation_type')->willReturn(0);
+        $parent->expects($this->once())->method('morphInstanceTo');
+        $parent->expects($this->never())->method('morphEagerTo');
+
+        $parent->relation();
+    }
+
     public function testMorphToWithSpecifiedClassDefault()
     {
         $parent = new EloquentMorphToModelStub;