The effects of aquatic exercise on various physiological and psychological outcomes have been well documented in children with cerebral palsy (CP) in recent years. However, few research specifically addressed how balance is affected by aquatic exercise. The purpose of this study was to investigate the effects of aquatic exercise on balance in children with CP. A case study approach with multiple data points was employed for this study. Three children with spastic CP (age seven to 14, GMFCS level I and II) participated in a 40-minute aquatic exercise three times a week for seven weeks. Each session included warm-up, static and dynamic balance training, mobility exercise, and cool-down. Balance outcomes were measured four times including pre, midcheck, post, and seven-week follow-up intervention. Biomechanical balance tests were administered on a computerized posturographic equipment (Smart Balance Master, Neurocom International, Clackamas, OR, 2010), which utilized dynamic dual forceplates with rotation capabilities and a movable visual surrounding. Comprehensive balance assessments were performed using various test protocols in the equipment, which were Sensory Organization, Motor Control, and Adaptation tests. The tests examined x multifaceted changes in static and dynamic balance, based on postural sways profiles, ground reaction force data and automatic postural response time under various conditions. Results were analyzed using visual analysis of trend graphs from each case. There were improvements observed in each participant that varied individually. The results suggest that children with CP can improve balance and balance-related motor adaptation skills through a seven-week aquatic intervention program. The interpretation of our study outcomes must be limited for generalization due to the nature of case study, as well as the large variability of physical conditions among children with CP.