Abstract: The preparation conditions of the absorbent modified with microwave-Ce (MBC) and the reaction conditions for low-concentration ammonia adsorption were optimized, and MBC were characterized by XRD, SEM and FTIR. The experimental results indicate that the inner structure of MBC has changed; specific surface area and the number of hydroxide radical have increased. The treatment effect for ammonia of loaded biochar is superior to that of biochar (BC) and the preparation conditions is optimum when solid-to-liquid ratio is 1:25 and pH of dipping is 10. The maximum adsorption capacity of ammonia reaches 11.297 mg/g when solution concentration is 50 mg/L, initial pH is 10, reaction temperature is 50℃, reaction time is 120 min, and absorbent dosage is 5 g/L. Its adsorption process conforms to the pseudo-second-order kinetics model.