Abstract: For the uncertainty problem of multi-attribute decision-making, the set pair analysis was made to deal with both the certainty and uncertainty problems. In view of the dialectic relation between certainty and uncertainty, the schemed index set and ideal index set were taken as a set pair to define the connectivity distance of generalized weight between all other schemes and the positive scheme as well as the distance between all other schemes and the negative schemes. Discusses the present applications of the set pair analysis in multi-attribute decision-making, with the deficiency in applications pointed out. Then a multi-attribute decision-making model was proposed on the basis of connectivity distance of generalized weight, and it was applied to the optimum decision of mine equipment. The results showed that the model is adaptable to multi-project optimization, thus providing a new way to the multi-attribute decision-making.