The total combined length of the Red and Orange Lines of the Kaohsiung Mass Rapid Transit System will be 42.7 kilometers (26.5 miles). Along these two lines, there will be 38 stations, of which 28 will be underground, two at ground level and eight elevated.

The project ran into significant construction delays due to a tunnel collapse in 2004 and 2005, and controversy over inhumane treatment of Thai migrant workers in 2005. These delays delayed the opening of the MRT considerably from the originally planned December 2006 date. The Sanduo-Siaogang section of the Red Line was eventually opened to the public for free test rides in February 2008, and the Red Line (except for 2 stations) opened for service in March 2008. The Orange Line fully opened for service on September 14, 2008.

Ridership has been far below expectations, with an average of 100,000 passengers per day versus an expected 360,000, and accumulated losses are expected to reach NT$6 billion by the end of 2009. Currently, as of November 2010, the average daily ridership stands at about 123,385, with ridership figures significantly greater on weekends than on weekdays. During New Year’s Eve on December 31, 2010, the system transported over 292,000 passengers. KRTC stated that ridership would need to exceed 380,000 passengers per day in order to break even.