The objective of this study was to assess the efficacy of botulinum toxin for upper limb spasticity in cerebral palsy. An open-label study was conducted in 11 children with cerebral palsy. Post-botulinum toxin assessment was conducted in weeks 1, 4, and 16, with averaged scores being analyzed. The Clinical Global Impression Scale of the mothers showed marked, moderate, and mild improvement in five, four, and two cases, respectively. The Modified Ashworth Spasticity Scale score showed a statistically significant decrease in the mean spasticity score (P < .003). Other tests were performed depending on the cognition of the child. Increase in joint motion occurred in all five children assessed using web space (P = .043). For the Jebson Hand Function Test, improvement occurred in all five cases assessed (P < .03). Four of five (80%) children could perform tasks that they failed before they were given botulinum toxin. Botulinum toxin is useful in decreasing spasticity and improving the upper limb function of young children with cerebral palsy with normal cognition. Motivated families should be selected with a specific target of using botulinum toxin as an adjunct in a habilitation program.