K-GMT Science Group (KGSG) is in charge of overall science operations with an aim to promote scientific activities of Korean Astronomical Community for the GMT era in 2020. KGSG is currently running and/or promoting K-GMT Science Program, K-GMT Science White Paper Initiative, and K-GMT Summer School for Young Researchers. KGSG is also planning to join several international survey projects such as SDSS IV and LSST. We will introduce the current status on various operations and the future plan for KGSG to the community members.