The objective of this study was to measure the effect of lower extremity multilevel botulinum toxin A injections and comprehensive rehabilitation on spasticity and to determine the functional gains in ambulatory children with cerebral palsy. Sixteen ambulatory children with spastic cerebral palsy (9 hemiplegic, 7 diplegic), aged between 3 and 8 years, who were able to walk with or without assistance (Gross Motor Functional Classification System I-III) were recruited to the study. Botulinum toxin A injections were applied to a total of 23 extremities, followed by a comprehensive rehabilitation program. Walking distance and walking speed (evaluated by the Six-Minute Walk Test) were significantly improved after treatment. Similarly, scores on the Observational Gait Scale (assessed by video gait analysis) increased significantly. Improvements in muscle length, spasticity, and selectivity were recorded. Reduced muscle spasticity after botulinum toxin A injections in children with cerebral palsy, with a comprehensive rehabilitation program, enabled clinically relevant improvements in functional ability.