Fundamental movement skills (FMS) proficiency is believed to influence children's physical activity (PA), with those more proficient tending to be more active. Children with cerebral palsy (CP), who represent the largest diagnostic group treated in pediatric rehabilitation, have been found to be less active than typically developing children. This study examined the association of FMS proficiency with PA in a group of children with CP, and compared the data with a group of typically developing children. Five FMS (run, jump, kick, throw, catch) were tested using process- and product-oriented measures, and accelerometers were used to monitor PA over a 7-day period. The results showed that children with CP spent less time in moderate to vigorous physical activity (MVPA), but more time in sedentary behavior than typically developing children. FMS proficiency was negatively associated with sedentary time and positively associated with time spent in MVPA in both groups of children. Process-oriented FMS measures (movement patterns) were found to have a stronger influence on PA in children with CP than in typically developing children. The findings provide evidence that FMS proficiency facilitates activity accrual among children with CP, suggesting that rehabilitation and physical education programs that support FMS development may contribute to PA-related health benefits. (Contains 3 figures and 2 tables.)