The Yamagata Zao Onsen Ski Resort (山形蔵王温泉スキー場, Yamagata Zaō Onsen Skī-jō) is the largest ski resort in Tōhoku region, Japan, operated by Zao Onsen Tourism Association (蔵王温泉観光協会, Zaō Onsen Kankō Kyōkai). The resort is mostly famous for its ski slopes in winter, but trekking is also popular sports in summer season.