Abstract: Chlorella is one of the single-cell algae that was studied, cultured and used for human. The current reiew of the interrelationship of product, quality, culture type, and media type for eco- nomically feasible system; the technical condition on climatological factors, carbonating, the need for mixing, seperating, harvesting and drying; and the progress of mass culture on Chlorella was summarized in this paper. The future development trends of mass culture will be automatic photosynthe tic reactor culture. The relationship of productivity and the solar energy conversion efficiency which is one of the main limitations on productivity was discussed also.