To construct the rational and scientific design scheme evaluation method for a target, on the basis of researching on the complement of the gray clustering theory and information axiom, applying the combination in the design scheme evaluation, a scheme evaluation method based on the grey clustering and information axiom integrated is put forward. Aiming at the defect of obtaining difficulty for evaluation indexes, the evaluation index system is constructed by using the analytical hierarchy process. Aiming at the shortcoming that qualitative indexes are not be evaluated by information axiom, the qualitative index is whitened by using the triangle whiten weight function. At the same time, the computational formula of the information amount is improved, and the design scope and system scope of design scheme are extended to make the calculation results more actual. The weight of each index in the evaluation process isn’t needed to provide, and the subjective judgment is avoided on the influence of the evaluation results. Taking the process of obtaining the optimal scheme for the mechanical parking equipment as an example, the proposed method is analysis verified. The application examples show that the optimal scheme satisfying user needs is got in a relatively short time by using this evaluation method and a theoretical basis is provided for the establishment of a scientific and rational evaluation method.