Introduction: Cerebral palsy treatment is complex and spends time and resources. Motor learning depends of repeated training and preserved cognition.

Methods: Cross-sectional study in cohort of hemiplegic cerebral palsy (HCP) treated with botulinum neurotoxin type A (BoNT-A). Data collected from charts and clinical evaluations. Statistical tests considered p<0.05.

Results: Sixty-six patients concluded all evaluations. Higher performance, verbal and total IQ had positive correlation with paternal education and the two last also with maternal. Normal sensory tests, especially two-point, presented relation with better performance, verbal and total IQ. Children with better verbal IQ were classified more frequently as level I on CFCS; as well as those with better performance IQ as level I on MACS and more frequently had GMFM-E>95%. Patients with better verbal IQ had larger spasticity reduction and better currents Mini-Mental, MVHT, muscle strength, SCALE, SCAUE, arm and hand Brunnstrom, PRS and UPRS. Children with better performance IQ had lower spasticity and better currents MVHT, muscle strength, SCALE, SCAUE, arm and hand Brunnstrom and UPRS. Patients with better Performance IQ had better total WeeFIM. Total IQ had positive correlation with currents Mini-Mental, MVHT, muscle strength, SCALE, SCAUE, arm and hand Brunnstrom, PRS and UPRS. They also had larger spasticity reduction.

Conclusion/Discussion: Better cognition is a main factor in HCP children outcome rehabilitation with better follow-up in motor functions, mainly hand activities and gait. Children with higher verbal and total IQ had larger spasticity reduction, being best responders to BoNT-A treatment.