The GS Caltex Maekyung Open, as it is known for sponsorship reasons, is a professional golf tournament that takes place in Seongnam, Gyeonggi Province, South Korea.

It was established in 1982,[1] replacing the Korea Open as the South Korean event on the Asia Golf Circuit.

[3] Since 2018, it has again been a fixture on the Asian Tour, except for 2020 and 2021 due to restrictions in place during the COVID-19 pandemic.

In 2005, Korean Choi Sang-ho won the tournament and set an Asian Tour record as the oldest winner on tour at 50 years and 145 days.

This tournament has generally been staged at the Nam Seoul Country Club.