BackgroundArm swing during gait is usually neglected, as it is not an essential component of walking that it spontaneously occurs, so there are doubts if it affects gait or not. The upper limb in hemiplegic cerebral palsy is more involved than the lower limb. The aim of this study was to enhance swinging of arm by using arm cycling and assess its impact on both upper and lower limb joints’ angular displacements during gait cycle of children with hemiplegic cerebral palsy. MethodsForty-eight hemiplegic cerebral palsy children participated in this study (18 boys, 30 girls) with an average age of 5.1±0.87years. Children were randomly assigned to two groups, study group (A) and control group (B). The study group received arm cycling in addition to gait training exercise, while the control group received gait training exercises only. Three dimensional (3D) motion analysis was used before and after the training program to evaluate the angular displacements of shoulder, elbow, hip, knee, and ankle joints during gait sub phases. ResultsResults showed a significant improvement (p<0.05) in arm swing. Improvement was manifested by decreasing flexion angular displacements of shoulder and elbow joints. Also there was a significant increase (p<0.05) in flexion angular displacements of the hip and ankle joints during gait cycle. ConclusionUsing arm cycling exercise is an effective method for improving both arm swing and leg angular displacements during gait of hemiplegic children.