This north-south line does not run through the city centre but links Gangnam directly to the northeastern districts of Seoul.

All trains on Line 7 are monitored by 1,008 closed-circuit television cameras that were installed in June 2012.

Construction on the two-station, 3.94 km (2.45 mi) extension to Seongnam began in 2013 and was completed on May 22, 2021.

A further seven-station extension to Cheongna International City station through Cheongna International City is currently planned and is not expected to open any earlier than 2027; the extension will allow for transfers to the airport railroad.

Another further two-station extension through Incheon's metropolitan landfill to Geomdan Oryu station is also currently being planned.