Base object model is upgrading technology of HLA OMT model, which is the new modeling standard in simulation interoperability. The composition of BOM template is firstly introduced, and the conceptual model is considered as the representation of BOM’s the high level modeling characteristic. The privileges of BOM comparing to OMT are analyzed. In the end, the transformation method from BOM to OMT based on XSLT is introduced; the application of BOM in constructing HLA simulations is studied; the corresponding relationship between BOM conceptual model and OMT model is listed.