The Izuhakone Railway Sunzu Line (伊豆箱根鉄道駿豆線, Izuhakone Tetsudō Sunzu-sen) is a commuter railway line of the Izuhakone Railway, a private railroad in Japan. The line connects Mishima Station in the city of Mishima with Shuzenji Station in the city of Izu, both within Shizuoka Prefecture. The name "Sunzu" comes from the former provinces of Suruga and Izu, although the line at present operates only within the borders of former Izu Province.