Climate change has led to frequent extreme weather and changes in precipitation patterns, which directly or indirectly affect the health and safety of urban street trees, resulting in potential hazards and high-risk uncertainty of urban street trees, and the risk management of urban trees is facing significant challenges. Improving the risk management capability of street trees is a crucial step to promote the civilized governance of cities. Based on the background of climate change, combined with the current practical experience and cutting-edge research on tree risk management at home and abroad, this paper analyzes the internal and external factors of street tree risk. To effectively evaluate the risk of street trees, a risk assessment model was proposed based on the correlation between each index factor and the risk level of street trees. Based on the theoretical analysis and logical reasoning of the model, comprehensively considering the growth environment and risk status of street trees, combined with the actual situation in Shanghai, this paper puts forward the coping strategies for the whole life cycle risk management of urban street trees: formulating tree species planning and strengthening theoretical research according to local conditions, actively exploring the street tree risk assessment method with multiple exposure factor indicators under climate change, improving the organizational structure and constructing a complete risk management system, and effectively discussing the management mechanism of street tree risk. In order to provide theoretical support for improving the management level of street trees in China and provide a practical reference for the government to formulate relevant systems and systems.