The present study was undertaken to compare the social-economic status and the home environment of both nonretarded and mentally retarded children (MR). In addition, the attitude of family toward the retarded children was investigated. The surveys were carried out twice, first in 1973 with the 299 MR subjects and then in 1980 with 657 MR subjects. An equal number of nonretarded students were selected as the comparative group. The main findings were as follows: 1) The social-economic status of MR group family were much poorer than that of the nonretarded group: The education level and median income level of the parents of the MR group were lower than those of the nonretarded group; the popularity density per living unit in the MR group family was greater than that in the non-MR group; and more parents of the MR group were employed in the unskilled jobs. 2) The deprivation of social and cultural experience for the MR group was more obvious than that of the nonretarded group. Specifically, the retarded students had poor experiences of traveling, had few toys and reading materials, and seldom had opportunity to attend kindergarten. 3) Only about half of the parents of the MR group recognized that their children were retarded; about one third of the parents hoped that their retarded children could attend senior high school after graduated from special classes. However, a small portion of parents rejected their retarded children. Clearly, the present study does suggest that specific enrichment or early education programs for socially disadvantaged children be necessary to reduce the prevalence of cultural-familiar retardation in the urban slum area of Taipei city.