The purpose of this study is to examine the laws and regulations related to the urban redevelopment of Marunouchi and, through the analysis of previous studies, identify key elements in creating low-rise public spaces in high-density urban areas. Based on the characteristics of the low-rise (31m in height) plan that has been maintained since the aesthetic improvement in 1923 and the contents of the urban redevelopment process in 1998, this paper analyzes the case of Marunouchi Building. Through this analysis, it seeks to identify the institutional and procedural elements that enhance the public nature of urban redevelopment, focusing on the low-rise planning in high-density urban spaces.