Aiming at the problem of how to quickly retrieve the relevant instance according to a certain degree of similarity in case reasoning design, this paper proposes a retrieval method based on fuzzy comprehensive evaluation.With object oriented case representation methods, we mainly study how to determine the similarity of attribute characteristics in mechanical design basis. The proposed retrieve method introduces fuzzy mathematics and grey relation analysis into the case retrieval process, and the combination weight of feature attributes are determined with the analytic hierarchy process and entropy value method. Taking the hoist design as an example, the efficiency, reliability and practicability of the proposed retrieve method are validated.
