Abstract: To consider different effects of risk factors on the risk assessment and to overcome the problem that qualitative evaluation information and expert remark under incomplete information cannot be utilized in the comprehensive risk evaluation for deep pit construction (DPC), a synthetic risk evaluation method for DPC is established based on the evidence theory. The index system of risk assessment for DPC is established on the basis of risk identification firstly. Then, the risk synthetic assessment model in the light of the evidence theory is proposed. In the assessment model, the weight of each stage factor is determined by using the analytic hierarchy process. The mass functions for calculating indexes are determined by expert remarks. The index mass functions are fused by the linear weighted method, and the decision rules are established based on the belief of the risk level. The proposed method is reasonable and practical, which is proved by an example, and it may provide reference for other similar projects.