Babies with mental retardation should be given comprehensive rehabilitation treatment. mental retardation in babies under 5 years old is the result of a comprehensive assessment through gross motor, language, and fine motor. If there is a delay in gross motor development, the baby should be given appropriate targeted scientific training after assessment according to the development pattern from head to tail, including physical exercise, waxing, fumigation, massage, sensory integration and other training. If the language function is backward, dysarthria test should be conducted and oral muscle training should be given; if there is a delay in fine motor development, corresponding training should be given according to the developmental pattern of hand function. Rehabilitation training should be carried out as early as possible, and the younger the age, the better the rehabilitation effect.