Abstract: The cultural relics environment impact assessment is the basic work to carry out environmental protection of cultural relics for construction project. At present, it is difficult to fully measure the comprehensive environmental impact of various factors on cultural relics during the construction and operation of construction projects and the impact level of construction projects on cultural relics. Considering the pollution emission factors during construction and operation of construction projects, and taking the cultural relics protection unit as the evaluation acceptor, a conceptual model of the impact of construction projects on cultural relics was constructed. Through systematic analysis of the main environmental pollution factors affecting the cultural protection unit, a comprehensive influence evaluation system was established, including four levels of essential vulnerability, source characteristics, exposure characteristics and cultural relics value characteristics, with 18 indexes, and the weight of each index was determined based on the combination weighting method. The comprehensive influence of a precast plant construction project in Gansu on the Great Wall Beacon Tower was evaluated by the constructed evaluation index system. It showed that comprehensive evaluation index was 4.160, indicating that the construction project would have a moderate impact on Beacon Tower.