Mathematical modeling is a time-consuming and error-prone task. To reduce modeler``s burden, many modeling methods for mathematical programming have been developed. However, most of the modeling methods are concerned little about the real world entities involved in mathematical models and do not support conceptual modularity such as hierarchical problem definition, buttom-up model construction from submodels, piecemeal approach to problem definition. To overcome the limitations, IMF(Integrated Modeling Framework) has been suggested, which provides a multi-facetted integrated modeling framework. The purpose of this thesis is to develop a methodology for representing and manipulating mathematical models in IMF. It provides subscriptfree indexing and factorable functions in order to enhance the simplicity and understandability in model construction and manipulation. Based on these ideas, a hypertext-based modeling environment called HyDSS is implemented, where models, data, and solvers are separated.