BOM(Bill of Material) is a description of parts, assemblies and raw materials that comprise a product structure. In manufacturing companies that produce various products with short life cycles, it is very important to manage to BOM of products with various options and versions efficiently. This paper describes an effective modeling and implementing technique of Generic BOM Management System(GBMS) for management of number of variant products. In this paper, OMT(Object Modeling Technique) was used to model a generic BOM and Object-Relational Database Management System(ORDBMS) was used to implement the GBMS database. In order to prove the effectiveness of proposed methodology, a case that assembles computer with various options was studied.