The Class ED78 (ED78形) was a Bo-2-Bo wheel arrangement AC electric locomotive type operated in Japan from 1968 until the 1990s.

[2] The locomotives were introduced to operate on the steeply-graded Ou Main Line between Fukushima and Yonezawa, which was converted from 1,500 V DC electrification to 20 kV AC in October 1968.

[3] All 14 locomotives were built by Hitachi in Mito, Ibaraki, with modifications to convert ED94 1 to ED78 901 carried out at JNR's Koriyama factory.

[4] It was then moved to a site adjoining Rifu Station in Miyagi Prefecture, and later moved to the nearby Sendai General Shinkansen Depot.

[4] It was moved to Hitachi's Mito factory in Hitachinaka, Ibaraki in 2015 and cosmetically restored in 2016.