Introduction. This study analyzed the association between psychomotor development and sociodemographic and family stimulation factors in 3-year-old children from San Carlos de Bariloche. Population and Methods. A total of 152 apparently healthy children aged 35-37 months old who attended municipal and private kindergartens were evaluated. Children's performance in personal-social, fine motor, language and gross motor skills development using the National Screening Test was analyzed. The relationship between environmental factors and the achievement of developmental milestones was studied using a multivariate logistic regression model. Results. Twenty seven percent of children did not pass the test. The most common outcome measures associated with altered developmental milestones were no reading, low birth weight, and the parents' lower education level. The association with reading was always positive; and this also occurred in relation to the parents' education level. A low birth weight had a negative association with the possibility of passing four milestones, three of which were gross motor skills. Children who attended municipal kindergartens had a low performance in three language milestones, one personal-social milestone and one fine motor milestone when compared to national profiles. Conclusions. The percentage of children who did not pass the test was 27%. The most common outcome measures associated with altered developmental milestones were lack of reading to the child, low birth weight, and the parents' lower education level.