Recently, building remodeling has been of more importance than ever, and it has become necessary to consider the economic efficiency in building remodeling. This study is intended to investigate the various aspects of remodeling and their comparative importance, based on the responses by building owners and remodeling constructors, and eventually the development of evaluation method of economic efficiency in building remodeling. The survey of office building constructors and building owners shows that. the need of remodeling is commonly stressed but their concerns differ. The proposed evaluation method may be useful to resolve the difference of economic concerns between demand and supply parts of remodeling, and give practical and reasonable guidelines to them.