Preventive conservation of museum cultural relics has made significant progress in China over the past more than twenty years of systematic research and application practice. In recent years, Shanghai Museum has introduced the concept of risk management into preventive conservation to reduce risk and to ensure the safety of cultural relics, through a clear process of establishing the context, risk assessment, risk treatment and monitoring and review. In this paper, two temporary exhibitions at Shanghai Museum are used as examples to elaborate on the application practice and to provide some thoughts on the preventive conservation and risk management of museum cultural relics from the perspectives of statistical analysis of environmental data, humidity threshold setting, selection of regulation strategies, assessment of the environmental safety of materials, and sealing performance of museum showcases.