The purpose of this study was to investigate the effectiveness of Johnstone pressure splints (JPSs) on spasticity and cutaneous sensory inputs in children with spastic cerebral palsy (CP). Thirty-four children with spastic diplegic CP participated in this study. Children whose motor development levels were similar were divided into a treatment and a control group. Each group consisted of 17 participants (six females and 11 males). Mean age of the treatment group was 48.82 months (SEM 4.42), and the control group, 47.52 months (SEM 5.27), The treatment group underwent Bobath's neurodevelopmental therapy (NDT) combined with JPSs. The control group underwent NDT alone five days a week for three months. Before and after treatments, lower-extremity passive range of motion (ROM) by goniometric measurements, spasticity by Modified Ashworth Scale (MAS), and somatosensory evoked potentials (SEPs) were measured. Passive ROM showed significant improvements in both groups (p < 0.01), In the treatment group, all MAS scores increased. In the control group, the difference was significant except for values of internal rotator muscles. Improvements in passive ROM in the treatment group were significantly higher than the control group except in hip abduction and external rotation (p < 0.05), MAS scores of the treatment group were significantly higher than the control group (p < 0.05). SEP values increased in both groups but values of the treatment group were significantly higher than the control group (p < 0.05).