The Kagoshima Main Line is a major railway line operated by the Kyushu Railway Company between Mojikō in Kitakyushu, and Kagoshima Station in Kagoshima City, at the southern end of Kyushu. Until March 13, 2004, it extended 393 km (244 mi) between its two termini; however, with the opening of the Kyushu Shinkansen on March 13, the section between Yatsushiro and Sendai was transferred to the third-sector Hisatsu Orange Railway Company. The line is an important line in Kyushu, connecting Fukuoka to many other major cities. It is the main line through the Fukuoka urban district, and as such many long-distance express trains from all parts of Kyushu use the section between Kokura Station (Kitakyushu) and Tosu Station, where the Nagasaki Main Line meets the Kagoshima Main Line.

Hisatsu Orange Railway Co., Ltd. is a third-sector railway company which operates Hisatsu Orange Railway Line in Kumamoto and Kagoshima prefectures. The line follows the former part of the JR Kyushu Kagoshima Main Line that connected Yatsushiro and Sendai in Kumamoto and Kagoshima Prefectures, known historically as Higo and Satsuma Provinces. The length of the line is 116.9 km.