***Motor development, cognition and language in infants who attend day care centers*** AIMS: To evaluate the acquisition of motor milestones in the first two years of life and the relationship between gross motor function and manipulation, cognition and language in infants who attend day care centers. METHODS: Cross-sectional study with a non-probabilistic sample of infants attending public and private day care centers in a city in southern Brazil. The Alberta Infant Motor Scale and the Bayley Scales of Infant and Toddler Development were used to assess the motor performance of each child. Descriptive statistics were used for the characterization of the sample and simple linear regression in three different age groups (group 1: between six and nine months; group 2: between 10 and 12 months; group 3: between 13 and 16 months) for the analysis of relationships between the variables gross and fine motor skills, cognition and language. RESULTS: We studied 63 infants between six and 16 months of age who did not present statistically significant differences in their biological and sociodemographic characteristics when the three stratified groups were compared. Most children did not acquire the developmental milestones in the period expected for their age group. There was correlation between the developmental scores, and the gross motor function was able to explain a large part of the variability in the fine motor function, cognition and language scores (R2ajust>0.5) over the first two years of life. CONCLUSIONS: The evaluated motor skills occurred generally late in the sample. The delay in the acquisition of gross motor milestones had an impact on the overall developmental skills, corroborating the influence of gross motor function in the other domains of development.