In 1976, a construction of the planned freight rail line of Japanese National Railways (JNR), called Seto Line (瀬戸線,Seto-sen?), began. However, the construction halted later due to the huge deficit of JNR. The line consisted of two separated sections, one between Setoshi and Kōzōji, another between Kachigawa and Biwajima. The construction of the both sections resumed later, as passenger lines but by different operators. The former section, the current Aichi Loop Line, was succeeded by Aichi Loop Railway, while the latter, the current Jōhoku Line, was succeeded by JR Central and TKJ. The first section of Jōhoku Line, between Kachigawa and Owari-Hoshinomiya, opened in 1991. The section between Owari-Hoshinomiya and Biwajima opened in 1993.
There is no rapid service. All trains make stop at all stations. The train runs extremely infrequently as a commuter rail line in large Japanese city, once per an hour in daytime, 2 or 3 times per an hour in morning and evening.