The line is connected via the JR Tōzai Line in downtown Osaka, at, to the Tōkaidō Main Line and Fukuchiyama Line. This link enables trains operated from Nara to the west, as Kobe, Himeji, and Sanda. Rapid services of several types of stops, with no surcharge, are also provided. Abbreviations are tentative for this article. ;Local ;Regional Rapid ;Rapid
The line was originally built and operated by the Naniwa Railway between Katamachi and Shijōnawate in 1895. Two years later, the Kansai Railway bought the line in order to have its own trunk line to Osaka from Nagoya, combined with constructing the section between Shijōnawate and Kizu. Katamachi Station was unable to be expanded, thus Amijima terminus was constructed. However Kansai Railway bought the Osaka Railway line from Nara via Ōji to Minatomachi in downtown Osaka, and shifted its main line to the ex-Naniwa Railway line. Thereafter, the Katamachi Line became a branch of the railway network of Osaka. The Shigino to Hanaten section was duplicated in 1927, with the Katamachi to Shigino section double-tracked in 1955, the Hanaten to Shijonawate section in 1969, extended to Nagao in 1979, to Matsuiyamate in 1989, and the balance of the section to Kyobashi double-tracked between 2007 and 2009. The section between Katamachi and Shijōnawate became the first Japan Governmental Railways electrified line in Osaka-Kobe-Kyoto area in 1932, with electrification extended to Nagao in 1950. After privatization of the then Japanese National Railways, the line became part of the West Japan Railway Company system, and the Kizu to Nagao section was electrified in 1989. In 1997, the JR Tōzai Line was opened and connected to Katamachi Line at Kyōbashi, and Katamachi Station was closed. Most trains began operating through to the Fukuchiyama Line. Converted from a freight branch to a passenger route, the Osaka Higashi Line began service in 2008. Trains from Nara via Kansai Main Line began operation to Amagasaki Station. However, these through trains to Amagasaki have now ceased operation since March 2019, with the Osaka Higashi Line extension.
Military use
Three military/weapons-related facilities used during the early 20th century were serviced by spurs located between and Tsuda Stations, between and Hoshida Stations, and the Osaka Army Arsenal warehouse between and Shigino Stations.
