The old wooden apartments which are considered as the lowest-quality housing in Japan has begun to show tendency of spontaneous renewal, in accordance with the decrease in the number of households living of these apartments. In order to predict future trend of such renewal activities, this paper analyzes the characteristics of the households living in those wooden apartments and their living conditioins, comparing ones of the new houses which spontaneously replaced the old wooden apartments. The study has been undertaken by case analyses in the periphery of the Osaka city. The conclusions of the study is summerized as follows. The detached houses and the row houses which were newly provided through apartments renewal are small-size dwellings, therefore are considerably overcrowded compared with other owned houses. Also the new fireproof apartments are smaller compared with other fireproof type in Osaka Prefecture. Consequently the number of members living in these fireproof apartments averages 1.7 persons only. On the other hand, almost all the households of one-room wooden apartments are single-persons. Another type wooden apartments called bunkajyutaku (with two or three rooms lacking adequate facilities for living) are usually occupied average-size households. The room density of these two types is significantly high; i. E. the tatami area per person is only 2/3 times as large as that of new houses or fireproof apartments. Therefore, although 22.8% of bunkajyutaku households occuppy two dwelling units, their living conditions have not necessarily been improved owing to the large-size of these households. In connection with such small-size dwellings or rooms, there is a fact that considerably large number of households can not secure dining or living room from bed rooms, nor ensure respective rooms for the grown-up children of different sex. It is among these apartments where officially defined substandard living conditions are frequently found.