The correlation of the ageing time of double-base propellant GATo-3 at 75 ℃（t_age） between the times needed for color change of standard methyl violet test （t_cch）and between the time-to-explosion of standard methyl violet tests at 120 ℃（t_exp）for aged and unaged samples is verified by variance analysis. Results show that (1)because statistic F＜F_0.99 for t_cch, the relativity between variables, t_age and t_cch is not obvious and t_cch can not be used as a criterion for evaluating the safety storage life of the propellant, (2)because F＞F_0.99 for t_exp, the relativity between t_age and t_exp is obvious and t_exp can be used as a criterion of evaluating the safety storage life of the propellant.