Abstract: Based on the in-orbit failure statistics of more than 100 modern small satellites which have been lunched by DFH Satellite Co., Ltd., it was found that the distribution law of in-orbit failures of domestic small satellites was Weibull distribution. An empirical formula was then presented using the in-orbit failure data of CAST968 and CAST2000 platforms. The failure distribution law and features of the full life-cycle of China’s small satellites were analyzed and summarized by integrating the study of failure distributions in the flight model phase of domestic small satellites. The failure probability density function (PDF) and the bathtub curves of full life-cycle of small satellites are given for the first time in China.