OOT is one of the main technological sustainments in software industry,the OMT will be the prominent model-constructing method in the software-developing area. In this paper,the OOT's essential characters and its'important meaning during the period of software-developing are discussed,the individual qualities of three kinds of models and the solid relations between each other are analyzed,the basic approaches of OOM in MIS are also pointed out. Moreover on this basis a modeling example built by this means is given in brief.