The aim of this study was to assess the effects of botulinum on spasticity of gastrocnemius and soleus muscles. Forty-one children with spastic cerebral palsy were assessed (muscle tone, range of motion of ankle joint extension with straightened and bent knee, and gait pattern using the Physician Rating Scale) before administration and 2, 6, and 13 weeks after. Changes on Physician Rating Scale and dorsiflexion with extended knee were significant after 2, 6, and 13 weeks. Differences in the remaining parameters were significant after the first two check-ups. Over 90% of the changes were positive. This research confirms the effectiveness of botulinum in reducing spasticity, increasing the range of motion, and improving the gait pattern.