An east-west railway along Korea's southern shore was long seen as a strategic route, but it took a number of attempts to complete the line.

[1] Following the 1961 coup, the Supreme Council for National Reconstruction started South Korea's first five-year plan, which included a construction program to complete the railway network, to foster economic growth.

[1] As part of the program, work began on a line to plug the gap between Jinju and Suncheon on April 28, 1962.

[4][5] On September 1, 2010, the South Korean government announced a strategic plan to reduce travel times from Seoul to 95% of the country to under 2 hours by 2020.

[13][14][15][16] The upgrade works also commenced at the junction with the Jeolla Line east of Suncheon,[17] this section opened on September 30, 2015.

Between Hyocheon and GwangjuSongjeong, to relieve congestion at road crossings in the city, the Gyeongjeon Line got a new alignment bypassing Gwangju to the south.

A new 44.8 km (27.8 mi) long branch from Hallimjeong Station was projected to improve freight transport connections to Busan's expanded port.

The 32.6 km long double-track cutoff had a budget of 1,396.15 billion won, and was implemented with private finance, the preferred bidder for the franchise was selected in July 2010.

[23] Construction of the 79.5 km long aingle-track branch commenced in 2002,[24] however, work was suspended in 2007 for lack of funds,[5] after having progressed to 5.5% of the 1,297.924 billion won budget.

[24] Construction resumed in 2015, plans were upgraded with the addition of electrification and a top speed of 200 km/h in 2019, with opening scheduled for December 2024.

[6] SRT also started operating high-speed services on the eastern ection to Jinju on September 1, 2023.