Abstract: With the development of 3D model definition technology, complete dimensioning plays an important role in digital product design and manufacturing. To ensure the integrity of design and processing data and achieve the automatic inspection of dimensioning completeness on 3D part＇s models, a novel algorithm of di- mensioning completeness inspection is proposed here based on the mapping relation in the parametric model- ing. First the mapping is established by analyzing the relation between sets of modeling parameters and engi- neering dimensions, and the mapping matrix is solved by Newton method. Then the mapping matrix is simpli- fied by the row elementary trans-formations, and the judge principle of dimensioning completeness is estab- lished by mathematic methods in the analysis of the relationship between the simplified mapping matrix and the dimensioning completeness. Finally, the algorithm for inspection of dimensioning completeness is devel- oped based on the judge principle. The correctness and effectiveness of the proposed approach is verified via the tests on some representative 3D parts based on the CAITA V5 system.