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, replacing the Korea Open as the South Korean event on the Asia Golf Circuit. Between 1999 and 2009 (except for 2004) it was a stop on the Asian Tour, and then in 2010 it became part of the OneAsia Tour schedule. 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.