The purpose of the present study is to investigate the association between certain family characteristics and schizophrenia. In order to examine the proposal, 404 schizophrenic pacients (201 males and 203 females) from 5 psychiatric hospitals situated in the great metropolilan area of São Paulo were observed. The majority of the pacients came from families very poor (85.74%). Over half the patients came from families of 4 to 8 siblings, and the average number of children per mother in those families was significantly higher (6.60) in comparison with the average figure for the population in general (4.65). Regarding the family disruption in about 55% of the cases this factor was present. As to the age of the patients at the family breakup, the majority of the subjects studied ranged from 0 to 3 years of age.