Abstract: Based on the concept of ' uncertainty management ' of the International Project Management Association, this paper sorts out the inherent technical advantages of BIM technology in improving the ability of 'uncertainty management'. A method of reducing information uncertainty and improving risk management ability through BIM technology is proposed. Taking the 1 million kW photovoltaic thermal power station of China Electric Power Construction Co., Ltd.as an example, the BIM technology is applied to all aspects of risk management. A refined BIM model of the heat absorption tower and construction platform is constructed. Based on this model, risk identification is carried out in a three-dimensional environment, and 13 main risk factors such as falling and collapsing are identified. Based on the BIM-FTA coupling model, the risk assessment and analysis are carried out to calculate the probability of safety accidents in the construction process. The results show that the key risks with high probability of accidents are mainly subjective human factors. Based on this, the project department uses BIM technology to take measures such as construction simulation analysis, safety measures analysis, VR safety education training and emergency management plan to improve personnel quality and reduce management loopholes. This study innovatively combines BIM technology with FTA to explore the transformation of risk management paradigm from 'passive response' to 'active control', which provides a scalable technical path for complex engineering safety management and control.