Abstract: Carbonate rock is the largest carbon sink on earth. Carbonate Weathering related carbon sink is listed as one of four carbon dioxide removal methods in AR5 report. Karst covers approximately 35% of the total area of China. The national carbon sink from carbonate rock weathering in new model is 0.051 Pg C/a, Karst carbon sink have been included in the national “Double Carbon Actio” plan as an important way to achieve carbon neutrality. This paper introduces the concept of karst carbon sink from three aspects: the development history, controlling mechanisms and research progress of karst carbon sink in China.