In the paper,the effects on Phaffia rhodozyma TY-I-8 caused by two different mutation agents of Ultrasonic and LiCl were investigated.The results of the experiments indicated that the mutation technology of ultrasonic-LiCl was one of the most effective techniques for the improvement of Phaffia rhodozyma.The optimum mutation time of Ultrasonic was 60min.The appropriate mutation concentration of LiCl was 0.2%.A mutant strain UL-2 with a better genetic stability and higher astaxanthin yield was gained by ultrasonic-LiCl complex mutagenic and reasoning method of diphenylamine.The production of astaxanthin was 856.72μg/g that was enhanced by 289.42% compared with that of the initial strain.