Abstract: The effects of nitrogen and phosphorus application on the yield of cluster redpepper and its other relevant characteristics have been studied through a two-year test，using saturated D-optimum design．The results show that phosphorus has larger effect on increasing the pepper numbers of a single plant than nitrogen；N and P have the similar effect onthe weight of a single pepper；N has larger effect on increasing the plant height than P；the shoot number decreases with the increase of P application and increases with the increase of N application；the yield responses show a parabola model to either N or P application According to the fertilizer response equation obtained，the suitable N and P₂O₅ applied is 281．1lkg／hm² and 82．11kg／hm² respectively to get the target yield of 4767 kg／hm² ．