Objective: To investigate the rehabilitation effect of sling exercise training (SET) on children with spastic cerebral palsy. Methods: From October 2017 to June 2020, 104 children with spastic cerebral palsy in the Department of Rehabilitation and Pediatrics were randomly divided into a control group and an SET group, 52 cases in each group. Both groups were given routine rehabilitation training, while SET group was given SET at the same time. Six months later, the rehabilitation effect was evaluated by modified Ashworth Scale (MAS), Berg Balance Scale (BBS) and Gross Motor Function Measure Scale-88 (GMFM-88). Results: Compared with the same group before the treatment, the MAS scores of adductors, gastrocnemius, and soleus in the two groups decreased significantly after 6 months of treatment, while the BBS score, GMFM-88 total score, and D, E functional area score increased significantly (P<0.05). Compared with the control group, the MAS scores of adductors muscle, gastrocnemius muscle, and soleus muscle in the SET group were significantly lower, and BBS score, GMFM-88 total score and D, E functional area score were significantly higher. The difference was statistically significant (P<0.05). Conclusion: SET can significantly reduce the lower limb muscle tension and improve the body balance ability and limb motor function in children with spastic cerebral palsy, which has significant rehabilitation effect.