Abstract: Information overload is widely exist in product design process. To alleviate the information overload, the main approach is to improve the accuracy of the search engine. The knowledge map can be used to achieve the goal by providing the knowledge association information. A semi-automation process of constructing domain knowledge map was proposed. In the process, the domain feature set was defined by domain experts to guarantee its comprehensiveness and independence, and the latent semantic analysis was adopted to eliminate the semantic overlapping in the feature set. Analyzed the distribution of the domain knowledge similarity, an ultimate domain knowledge map was built with a middle-distance strategy. At last, a knowledge map for computer numerical control (CNC) domain was constructed by the proposed method to demonstrate the feasibility.