△ : Only rapid and regional rapid through trains to and from the JR Tozai Line return at Tsukaguchi Station in the non-rush hour.
| : All trains pass
Local : Stops at all stations, a majority of them operate through services to the JR Kyoto Line, but only these trains stop at Tsukamoto Station. The remaining services operate solely within this line. Rapid : Mainly operates between Osaka and Sasayamaguchi. Some trains operate through services to/from the JR Tozai Line via Amagasaki Station. Among these through trains, some return at Tsukaguchi Station in the non-rush hour. Tambaji Rapid : Operates between Osaka and Fukuchiyama. Regional Rapid : Operates between Osaka and Sasayamaguchi or between Osaka and Shin-Sanda. Also through services to/from the JR Tozai Line and the Gakkentoshi Line.
The Japanese Government Railways opened the Osaka - Kobe section of what is now the Tokaido Main Line in 1874 as a dual track line. The Kawabe Horsecar Railway opened a 762mm gauge line between Amagasaki and Itami in 1891. In 1893, the horsecar railway was reorganized as Settsu Railway, which introduced steam power to the railway and extended the line to Ikeda. The Settsu Railway was merged by Hankaku Railway, which had a plan to build a railway between Osaka and Maizuru. The Hankaku Railway converted the line to 1067mm gauge and extended it to Takarazuka in 1897 and to Fukuchiyama in 1899. The company also connected the line to the Kanzaki Station of the JGR line in 1898 making the line to the original Amagasaki terminal a branch. Hankaku Railway was nationalized on August 1, 1907. The Amagasaki - Tsukaguchi section was duplicated in 1934, and extended to Takarazuka in 1979/80. The Takarazuka - Shin-Sanda section was duplicated in 1986 in conjunction with the opening of the 2970m Najio tunnel and associated deviation, which shortened the route by 1.8 km. Duplication to Sasayamaguchi was completed in 1996. The Amagasaki - Tsukaguchi section was electrified in 1956, and extended to Takarazuka in 1981. The remainder of the line was electrified in 1986. CTC signalling was commissioned between Fukuchiyama and Sasayamaguchi in 1982, extended to Hirono in 1984 and to Amagasaki in 1986. The branchline between Amagasakikō Station and Tsukaguchi Station ceased passenger operation in 1981 and freight operation in 1984.
Former connecting lines
Sanda station - The 12 km line to Arima operated from 1915 to 1943.
Sasayama-guchi station - A 5 km line to Sasayama-Cho opened in 1914. During World War II the Japanese became concerned about the vulnerability of the Sanyo Main Line to naval attacks. A bypass was proposed from Sasayama-guchi to Sonobe on the Sanin Main Line utilising the line to Sasayama-Cho, which was extended 13 km to Fukuzumi in 1944. The remainder of the proposed line was not built due to the cessation of hostilities. The line closed in 1972.
Fukuchiyama station - The Hokutan Railway Co. operated a 12 km line to Koumori between 1923 and 1971.
Accidents
On April 25, 2005, a seven-car 207 series train on a Rapid service derailed and crashed into a building between Tsukaguchi and Amagasaki on its way for Doshisha-mae via the JR Tōzai Line and the Katamachi Line. 107 passengers were killed in the accident. Operations on the affected part of the line remained suspended until trial runs began on June 7, 2005. Passenger service resumed on June 19, 2005. The train involved was train number 5418M, a limited-stop "Rapid" commuter service from to. It was a seven-car 207 series electric multiple unit formation consisting of a 4-car set and a 3-car set coupled together. The train was carrying approximately 580 passengers at the time of the accident.