Abstract: Nowadays the inefficiency of nitrogen and phosphorus removal is a common problem in wastewater treatment，and the primary reason is that the wastewater has high amount of organic content but low amount of biodegradable organics． The biodegradable organics is one sort of important carbon source during biological nitrogen and phosphorus removal process． Solid wastes has the characteristics of high amount of organic content，easily biodegradation，reasonable price，using waste solid as external carbon source is promising to improve efficiency of nitrogen and phosphorus removal in wastewater treatment． The research introduced the characteristics of solid wastes including sludge，agricultural wastes，aquaculture waste and kitchen wastes，analyzed the status of using their hydrolysate as carbon source，and proposed the existing problems and further research．