Abstract: Based on the principle of analytical hierarchy process (AHP), an incomplete hierarchy model for the evaluation of design schems of rocket launchers is built up. According to the characters of this model and applying the theory of fuzzy membership functions, an improved algorithm is proposed. The result shows that, with the original algorithm, being loaded down with trivial details, it is often necessary to organize experts to construct pairwise comparison matrices. This can be avoided with the new scheme, thus a real-time evaluation scheme and a quasi-judgment without expert decision can be realized. The evaluation process can provide referent evidence for further optimizing design scheme.