Abstract: In the process of the liposome freeze,the ice crystal will not only damage the liposome,but also influence the heat and water vapor transfer.The freeze dried quality of liposome suspensions at different cooling rates are studied.The liposome temperature curve,water content curve and the ioposome size are compared.The results show that the quality of the freeze dried liposome frozen at the rapid cooling rate is better than that frozen at the slow cooling rate.