Abstract: In this paper, authors present a kind of relational data structure which is used to describe 3D industrial objects. Thus, the relational matching problem results in the problem of relational isomorphism or consistent labelling. In the procedure of consistent labelling, authors present three pruning algorithms, that use the multi-constraint, one to one correspondence constraint of relational data structure, the correspondence between relation-label tables and unit-label tables as the konw ledge to prune the searching tree. These approaches simplify the problem of relational isomorphism or consistent labelling in relational matching. Finally, an example and its discussion are given.