In response to the difficulty in quantifying the qualitative evaluation of open-pit mine blasting safety, a open-pit mine blasting safety evaluation model based on combination weighting and interval approximation is proposed to improve the accuracy of the evaluation results. Firstly, based on the actual blasting engineering, 15 influencing factors were selected to construct a safety evaluation index system for open-pit mine blasting; Secondly, based on the idea of combinatorial weighting, the subjective and objective weights calculated by G1 method and improved CRITIC method are coupled to obtain balanced and reasonable comprehensive weights of indicators. Then, based on the interval number theory, the number of evaluation intervals for indicators is determined to avoid the problems of discontinuous data and easy loss and distortion of indicator information in traditional qualitative evaluation point estimation methods. By calculating the deviation distance of a single indicator and the comprehensive deviation distance, the blasting safety level is comprehensively judged; Finally, taking 5 open-pit mine blasting examples in Hunan Province as the research object, the combination weighting interval approximation method is applied for comprehensive analysis. The results showed that the blasting safety level of all 5 mines was "relatively safe", and the evaluation results were in line with reality, verifying the applicability of the model in the safety assessment of open-pit mine blasting.