Aim: The aim of this study was to assess the effectiveness of Functional Electrical Stimulation in upper limb rehabilitation in children with cerebral palsy. Methods: 90 children with spastic cerebral palsy, age between 6 and 9 years, were randomized into two groups. 45 children, represented the control group, performed conventional physical and occupational therapy and robot-assisted therapy. In addition to the control group, the experimental group received functional electrical stimulation interventions with postural control on the affected upper limb. Results: The experimental group’s motor performance after treatment (improved coordination by 8.2%, wrist flexion by 9.75°, three-fingered grasp strength by 1.04°, and functional limitation lowered by 5.93) was considerably better than the control group’s which coordination increased by 5.5%, wrist flexion by 8.72°, three-fingered grasp strength by 0.7 and functional limitation decreased by 2.33. Conclusions: Functional electrical stimulation intervention was found to be an effective manner to improve motor performance, in terms of coordination, range of motion, and three-fingered grasp strength, visibly reducing functional limitation and improving performance in activities of daily living.