diff --git a/php/src/GildedRose.php b/php/src/GildedRose.php
index 1dcba599..608ede3b 100644
--- a/php/src/GildedRose.php
+++ b/php/src/GildedRose.php
@@ -27,6 +27,8 @@ final class GildedRose
         ・引数のsell_inを-1する
         ・計算後sell_inが0未満の場合、quality+2する
         ・計算後sell_inが0以上の場合、quality+1する
+        [商品：Sulfuras]
+        ・sell_in、qualityどちらも変更しない
     */
 
     /**
@@ -38,6 +40,9 @@ final class GildedRose
             if ($this->item->name === 'Aged Brie') {
                 // 商品：Aged Brieの処理
                 $this->agedBrie();
+            } elseif ($this->item->name === 'Sulfuras, Hand of Ragnaros') {
+                // 商品：Sulfurasの処理
+                $this->sulfuras();
             }
         }
     }
@@ -56,6 +61,14 @@ final class GildedRose
         }
     }
 
+    /**
+     * 商品：Sulfuras計算処理
+     */
+    private function sulfuras(): void
+    {
+        // 何もしない
+    }
+
     /**
      * sell_inの減算を行う
      */
diff --git a/php/tests/GildedRoseTest.php b/php/tests/GildedRoseTest.php
index d38c3f01..0be1cbc3 100644
--- a/php/tests/GildedRoseTest.php
+++ b/php/tests/GildedRoseTest.php
@@ -67,6 +67,39 @@ class GildedRoseTest extends TestCase
         $this->assertSame(50, $items[0]->quality);
     }
 
+    /**
+     * Sulfuras：sell_inが1以上、qualityが80
+     * 期待値：sell_in、qualityどちらも変更なし
+     */
+    public function testSulfurasNormal(): void
+    {
+        $items = [new Item('Sulfuras, Hand of Ragnaros', 5, 80)];
+        $gildedRose = new GildedRose($items);
+        $gildedRose->updateQuality();
+        $this->assertSame('Sulfuras, Hand of Ragnaros', $items[0]->name);
+        $this->assertSame(5, $items[0]->sell_in);
+        $this->assertSame(80, $items[0]->quality);
+    }
+
+    /**
+     * 複数商品
+     */
+    public function testMixCase(): void
+    {
+        $items = [
+            new Item('Aged Brie', 5, 10),
+            new Item('Sulfuras, Hand of Ragnaros', 5, 80),
+        ];
+        $gildedRose = new GildedRose($items);
+        $gildedRose->updateQuality();
+        $this->assertSame('Aged Brie', $items[0]->name);
+        $this->assertSame(4, $items[0]->sell_in);
+        $this->assertSame(11, $items[0]->quality);
+        $this->assertSame('Sulfuras, Hand of Ragnaros', $items[1]->name);
+        $this->assertSame(5, $items[1]->sell_in);
+        $this->assertSame(80, $items[1]->quality);
+    }
+
     // テストエラーの原因が特定できないので後で調査する
     /*
     public function testApproveArray()