In order to recommend a preferred highway route proposal with the best traffic safety performance, alternative proposals with the same level of details are compared qualitatively and quantitatively for safety audit. To obtain fair, objective and comprehensive audit results, and avoid inconsistent conclusions drawn by different units and auditors, a unified evaluation indicator system and a fuzzy comprehensive safety evaluation model were proposed . To demonstrate the effectiveness, the proposed method was applied in one highway alternatives audit and a reliable alternative audit result was produced. The model will be a safety comparison method cited by Technical Specifications for Highway Safety Audit (T/ CECS G: E10-2021).