Baby swimming pools are expanding rapidly. More and more citizens are concerned about the water environment quality of swimming pools as well as the health and security of infants swimming. According to the current situation of baby swimming pools, the key technologies of filteration and disinfection of existing water cycle treatment system were reviewed, such as sand filters, activated carbon filters, diatomite filters, membrane filtrations, and the usual disinfection equipments as well as several combined disinfection technologies. Combined with the needs of high water quality by infants' skin, the water treatment units and cycling ways of baby swimming pools should be designed according to the water features, while analyzing the proper key technologies used in each unit to ensure the safe, nontoxic and cleaning water quality, thereby, to build up an economical and easy to operate water cycle treatment system.