Background and Objective: Achievement of motor skills is an important part of childhood development. There are some scales that commonly used for preschool-aged children including Peabody Developmental Motor Scales, 2^nd edition (PDMS-2). A cross sectional study designed to compare motor skills of high risk and normal infants of 3 to 6 months of age.

Methods: In this case control study, 45 high risk infants 3-6 month of age were compared with 45 normal cases that matched for age and sex, for evaluation of motor development by PDMS-2. Subjects were selected by cluster sampling from different health centers of Tehran. Data about gross, fine and total scores were analyzed using SPSS software version 13.

Results: There was a significant difference between gross, fine and total motor scores in normal and high risk infants with perinatal risk factors (P<0.05).

Conclusion: Fine, gross and total motor scores in normal and high risk infants of 3- 6 months old are significantly different. It is recommended to evaluate movement development by PDMS-2 in mentioned infants and starting rehabilitation as soon as possible