Abstract: The evaluation of regional geological environment carrying capacity has important practical significance for improving the ecological environment, protecting the ecological environment and promoting regional sustainable development. A three-way decision model based on intuitionistic fuzzy is proposed to solve the problem of classification division in the evaluation of geological environment carrying capacity. The main contribution is that the relative loss function combined with conditional probability based on grey relational degree establishes the classification rules of intuitionistic fuzzy three-way decision. Finally, the feasibility of the model and the validity of the sorting rules are verified by comparative analysis.