Graphitic phase carbon nitride was used to degrade ammonia nitrogen in water,and the effect of the material in degrading ammonia nitrogen was investigated.Then,the effects of different initial pH and different initial ammonia nitrogen content on ammonia nitrogen degradation under xenon lamp illumination were explored.The results showed that under xenon lamp irradiation,when the initial pH=12 and the initial ammonia nitrogen content was 5µ g,the graphitic phase carbon nitride has a good degradation effect on ammonia nitrogen.When the initial pH=13,the initial mass of ammonia nitrogen was 7.5 µg,and after photocatalysis for 2 h,the removal rate of ammonia nitrogen was 95.68%.Through pseudo-first-order kinetics,it can be seen that graphitic carbon nitride has a good degradation rate of ammonia nitrogen under alkaline conditions.This may be attributed to the presence of more OH-and·OH in the solution as the initial pH increases,thereby enhancing the photocatalytic effect.