Using 17 illustrations and 25 charts, studies of various aspects of the increase of the number of television sets in Japanese families are introduced. First, the spread is studied chronologically following each period and the trend of each stage is investigated. Especially, the factors closely related to the increase, such as, wide use of radio sets, number of television sets purchased, fluctuation of prices, numbers of new television broadcasting station established, expansion of coverage of television stations and increasing number of registered receivers in each period, are carefully studied. Next, geographical studies of the increase including study by prefecture, that of urban and surburban area, and that of local areas covering the conditions of cities, towns and villages, are presented. Also, relationships with developing mass media, such as, newspapers, magazines, movie films and music records, are considered together with changes of advertising expenses by each media. Then, research on the development of economic conditions and trends of the rationalization of Japanese farmer, which are enabling them to purchase television sets, are conducted. The research includes study of ratio between hours spent for farm labor and those for the rest of daily life. The increasing number of farming machines as their production properties has been also investigated. Finally, studies on the development of television sets by profesfion are conducted. Especially, the difference in ratio of the increase of durable consumer properties between urban laborers and farmers as well as the difference in the degree of the improvement of consumption standard and the changes of income between the two groups are carefully studied.