diff --git a/src/Illuminate/Contracts/Database/Eloquent/Castable.php b/src/Illuminate/Contracts/Database/Eloquent/Castable.php
index e3f1bccda411..8656646f14da 100644
--- a/src/Illuminate/Contracts/Database/Eloquent/Castable.php
+++ b/src/Illuminate/Contracts/Database/Eloquent/Castable.php
@@ -7,7 +7,7 @@ interface Castable
     /**
      * Get the name of the caster class to use when casting from / to this cast target.
      *
-     * @return string
+     * @return string|\Illuminate\Contracts\Database\Eloquent\CastsAttributes|\Illuminate\Contracts\Database\Eloquent\CastsInboundAttributes
      */
     public static function castUsing();
 }
diff --git a/src/Illuminate/Database/Eloquent/Concerns/HasAttributes.php b/src/Illuminate/Database/Eloquent/Concerns/HasAttributes.php
index 609ff1f65c79..b01069f4f5a6 100644
--- a/src/Illuminate/Database/Eloquent/Concerns/HasAttributes.php
+++ b/src/Illuminate/Database/Eloquent/Concerns/HasAttributes.php
@@ -1066,7 +1066,7 @@ protected function resolveCasterClass($key)
 
         $arguments = [];
 
-        if (strpos($castType, ':') !== false) {
+        if (is_string($castType) && strpos($castType, ':') !== false) {
             $segments = explode(':', $castType, 2);
 
             $castType = $segments[0];
@@ -1077,6 +1077,10 @@ protected function resolveCasterClass($key)
             $castType = $castType::castUsing();
         }
 
+        if (is_object($castType)) {
+            return $castType;
+        }
+
         return new $castType(...$arguments);
     }
 
diff --git a/tests/Integration/Database/DatabaseEloquentModelCustomCastingTest.php b/tests/Integration/Database/DatabaseEloquentModelCustomCastingTest.php
index 2e72a54910dc..5df983887fd8 100644
--- a/tests/Integration/Database/DatabaseEloquentModelCustomCastingTest.php
+++ b/tests/Integration/Database/DatabaseEloquentModelCustomCastingTest.php
@@ -130,6 +130,12 @@ public function testWithCastableInterface()
         ]);
 
         $this->assertEquals('argument', $model->value_object_caster_with_argument);
+
+        $model->setRawAttributes([
+            'value_object_caster_with_caster_instance' => serialize(new ValueObject('hello')),
+        ]);
+
+        $this->assertInstanceOf(ValueObject::class, $model->value_object_caster_with_caster_instance);
     }
 }
 
@@ -155,6 +161,7 @@ class TestEloquentModelWithCustomCast extends Model
         'options' => JsonCaster::class,
         'value_object_with_caster' => ValueObject::class,
         'value_object_caster_with_argument' => ValueObject::class.':argument',
+        'value_object_caster_with_caster_instance' => ValueObjectWithCasterInstance::class,
     ];
 }
 
@@ -249,6 +256,14 @@ public static function castUsing()
     }
 }
 
+class ValueObjectWithCasterInstance extends ValueObject
+{
+    public static function castUsing()
+    {
+        return new ValueObjectCaster();
+    }
+}
+
 class Address
 {
     public $lineOne;