The purpose of this study is to analyze under-used properties in the old hillside residential area in terms of the urban tissues like building, plot, street and block. This study suggests 4 stages of analysis as following. First, this study draws the spatial decline index of urban tissue from the related laws, as construction year over 20 years, unauthorized house, undersized plot, plot without adjoining road, and plot with slope over 15°. Second, based upon the spatial decline index, this study analyzes the urban tissue elements of 7 dong residential areas surrounding old downtown in Busan. Third, this study tries to analyze and the negative impacts of urban tissue elements which are relevant with vacant space. Fourth, based on the analysis of the negative impacts of urban tissue elements, his study proposes the utilization methods of under-used properties through policy improvement and relaxation of legal regulation.