Industrialization and Urbanization in the European countries in the 19th century gave rise to various urban problems in regard to public hygiene, poverty, housing and social infrastructure etc. These problems forced to the urban governments to solve them and to transform the administration system. In German big cities, the benefit administration (Leistungsverwaltung), which aimed to secure the existence of urban population (Daseinsvorsorge), developed from the end of the 19th century. The urban government reorganized poor relief on the one side, and supplied water, gas and electricity on the other side. In addition they expanded the transportation system. The German type of welfare state has been described as "social state (Sozialstaat)". J.Reulecke called the development and reorganization of the urban administration in Germany before the First World War as "social city (Sozialstadt)", and stressed its role as the forerunner of "social state", which came into effect from the Weimar Republic era. This paper aims to clarify the characteristics of "social city", and its historical relation to "social state".