Fischer-Tropsch synthesis is one important technology for gas to liquid (GTL). The activity and selectivity of catalyst are key factors in this process. At present, there are mainly two kinds of catalysts, iron-based and cobalt-based, for it. The Co-based catalysts have attracted increasing attention due to their high activity, selectivity and performance stability. The characteristic and development of Co-based catalysts are reviewed, and the factors affecting the activity and selectivity of catalysts are analyzed.