The is a commuter railway line in Kanagawa Prefecture, Japan, operated by the private railway operator Izuhakone Railway. The line connects Odawara Station in the city of Odawara with the Daiyà «zan Station in the city of Minamiashigara.
, the line is operated using a fleet of seven three-car 5000 series electric multiple unit (EMU) trainsets.
The line opened on October 15, 1925, as the Daiyà «zan Railway, between and Daiyà «zan Station, with a track gauge of and an overhead power supply of 600 V. The terminus of the line was moved from Kari-Odawara to , close to the present-day Midorichà  Station on April 10, 1927, and finally to Odawara Station on June 16, 1935. The Daiyà «zan Line was merged with the Sunzu Line on August 23, 1941, and became part of the Izuhakone Railway from June 1, 1957. From November 25, 1976, the power rating on the line was raised from 600 volts to 1,500 volts. Automatic ticket gates were installed on all stations by 2003, and were upgraded to accept both the Suica and PASMO IC Card systems by March 2007.