Aiming at the problem that the incomplete tolerance specification results in the inspectors putting forward various certification schemes,which may make the design intention of the specification inconsistent with the verification scheme,taking the typical cylindricity in engineering as the research object,an ontology-based automatic identification method for cylindricity specification completeness was proposed.According to the mapping relationship between cylindricity specification and verification,an automatic identification engineering semantic model was constructed.The engineering semantic model was transformed into an ontology model based on description logic,and an algorithm for automatic completeness identification was proposed.Finally,the effectiveness of the proposed method was verified by combining the algorithm in an example.The results show that this method can effectively identify the completeness of cylindricity specification automatically.