The purpose of this study is to find and investigate the urban planning in the past, which led to the formation of Yokkaichi City. I think the following three plans are important. The first is a city-planning map 1941. The second is a master plan of the war rehabilitation land readjustment project. The third is a conception picture of the Yokkaichi general development plan 1960. I investigate into the city-planning map 1941 in this paper. This map was made by Mie Local City Planning Commission. According this plan, the southern part of Yokkaichi central urban district was developed as industrial district, and Yokkaichi station of Kansai Express Railway was transferred to where present Kintetsu Yokkaichi Station is located. This map played an important part to develop Yokkaichi City as an industrial-city, just like a master plan of those days. That was the first time Yokkaichi City had something like a master plan for the development of the city.