According to the risk identification and control requirements for spacecraft assembly process, a risk management model based on data processing has been suggested. The model is based on the data from product management software, and the design change times, the number of process documentation alternation, the number of tooling failure to meet requirements are selected as risk evaluation indexes. According to the empirical formula, all risk quantitative indicators in each period are calculated, and the corresponding risk control measures are took. The risk management model has been applied successfully in China’s spacecraft assembly. For the situation in a remote sensing satellite assembly, although the cycle time reduction was compressed by 25%, zero defects have been achieved during the assembly, which indicates the effectiveness of the method in risk control of the spacecraft assembly process.