Tuanbowa Reservoir is a saline-alkaline man-made lake in the North China plain.The results of comprehensive multidisciplinary investigation show that the nutrient salts are low in content, the planktonic species small in numerf and low in biomass, but the each very rich in periphyton resources.The emergent vegatation, Scirpus spp.and Phragmiies communis, is the main primary producer.The reservoir has a great potential for fishery production.It is concluded that the structure of fish composition should be adjusted so as to rationlly utilize renewable resources and to balance fishery development against environmental stability.