Article 1 of Building Code says that the purpose of this code is to execute building regulation for taking care of public safety, public traffic, public health, and city's image. According to the main idea of Article 1 of Urban Planning Law, it is deliberated on the purpose of promoting the balance development among city, township, county, and village. WHO proposes four things-safety, health, convenience, and comfort as the guidelines of environmental planning. After 1995's Kobe earthquake, safety, energy, charm, and mutual activation served as the basic factors in reconstruction plan. The Therefore, it is pretty sure that "safety" is thought the most important thing in urban planning from both domestic and international viewpoints. Based on "safe city", to build a comfortable, convenient, and livable disaster prevention toward 21st century. This article will coordinate "the research on building the frame of urban disaster prevention system" (Huang 1997A) and "the research on the content of urban disaster prevention system" (Huang 1997B). Then, through taking the disaster prevention review and improvement system in Tokyo city plan into .