Urban Planning Law and Building Act are the two main bodies of law which determine the quality of urban environment, the former controls the development of urban both qualitatively and quantitatively, the latter primarily guards public safety. However, the current regulatory regime which regulates urban building space, either by way of land use control or building safety management, are primarily composed of specifications which are lack of flexibility in governance, results in negative impact of urban transformation vitality and social development driven by supply and demand. This study focuses on the situation of the management of building use change in six municipalities in Taiwan, through documentation research and expert questionnaire, to explore the professional views of responsible staff at competent authorities and architects who have previously been engaged to conduct the change of building use, all with more than three years of experience. To analyse those views of the professionals on the current management system through principal-component-factor method under the premise of environmental quality as well as public safety, we conclude the key factors affecting the change permit of building use demanded by social development. Based on this study, ＂the requirements on two straight staircases＂, ＂the requirements on the number and width of refuge exits＂, ＂the restrictions on the change of straight staircases to safety staircases or special safety staircases＂, ＂ the requirements on barrier-free facilities for public buildings＂ and ＂the requirements on parking space＂ considered by professionals to be the top five difficult regulatory factors to comply with, are the key factors affecting the success of supply of social development demand, which shall provide a basis for the following research of transformation of our regulatory regime of urban building management.