Steam engines originally ran on the tracks; in the 1920s the line was electrified, following a trend of many railways in the area.
It was absorbed by Mie Railway (Santetsu) in 1931, who built and operated the nearby Utsube Line which also originated from Suwa Station at that time.
Kintetsu developed a plan to straighten the line as well as enlarge Suwa Station, which would be moved about a kilometer to the west.
When Kintetsu acquired the line the following year, it was relatively painless to tie the two lines together and it soon began offering limited express service directly from Uehommachi in Osaka and Nagoya to Yunoyama, aimed at attracting tourists to the onsen and nearby Mount Gozaisho.
Limited express trains that originated at Kintetsu-Yokkaichi continued to run the length of the Yunoyama Line for a few more years, but this service was ended in 2004.
Local (普通 futsū) Limited express service on the Yunoyama Line ended in 2004.