The aim of this study was the quantification of outcomes on gait pattern of isolated gastrocnemius fascia lengthening treatment in children with cerebral palsy over time using gait analysis. Twelve children with cerebral palsy were evaluated with gait analysis before and after gastrocnemius fascia lengthening, in different follow-up sessions (from 3 to more than 25 months after treatment). Twenty healthy children were included as controls. Data analysis showed significant improvements in ankle and knee kinematics and in ankle kinetics over time. The results showed that isolated gastrocnemius fascia lengthening improved lower extremity function without producing functional muscle weakness over time.