The is a Japanese railway line connecting Kiyama Station (on the Kagoshima Main Line), Kiyama and Amagi Station, Asakura. This is the only railway operated by the third-sector railway company . The company, and sometimes the line, are also called .
The line was opened on April 28, 1939 by the Japanese National Railways (JNR) as the Amagi Line, in order to supply military equipment to . In 1981, the line was named a specified local line and considered for closure. Freight services ceased in 1984.
On April 5, 1985, it was agreed that the line would be transferred to a newly created . Amagi Railway was thus created and inherited the former JNR line on April 1, 1986. While the conversion of the line into a bus route was unopposed by both Saga and Fukuoka Prefectures due to the Nishitetsu Amagi Line's existence, the municipalities Amagi and Miwa requested the line be kept in operation. After the transferring of the line, Ogà Âri Station was relocated by 400 meters to allow easier connection to the Nishitetsu Ogà Âri Station. The number of services were increased from seven return trips a day in 1982 to 42 in 2023 on weekdays. The AR400 series in use on the line is planned to be replaced by the ARe500 series starting from 2025.