Abstract: To meet the demands of the study of CFCs alternatives and the engineering application,a group contribution method is proposed to calculate the saturated liquid's density of freon in ethane class based on the equation of saturated liquid density of Перелъщтейн.On condition that the critical temperature and critical density or critical specific volume are known,the density of saturated liquid can be calculated with high accuracy.The obtained mean deviation and the maximum one are less than 1% and 15% separately,which can meet the demands of alternatives' studies and application.

Key words: group contribution method, freon in ethane class, density of saturated liquid