This experimental treatment model was designed for a reactive attachment disorder(RAD) by occupational therapiests in the children psychiatric area. In 1980, RAD was introduced as a diagnosis in the DSM-III by the American Psychiatric Association. The main features of RAD are lack of age-appropriate signs of social responsiveness such as poor eye contact and no interest in play. It is due to failure to form a attachment bonding between the mother and her baby. We organize a treatment group. There are 3 to 5 RAD patients aged 2 to 3, their mothers and 3 the rapiests . Most of them underdeveloped and still in the sensory-rooter stage level. Therefore, we attuned them through free play at the level of sensory-motor stage. The therapiests are eager to be a good attachment figures, after then help the patients to expand their interactive relationships to their own mothers. As a result, this group therapy at the level of sensory motor stage is very effective to RAD patients find also useful to differentiate RAD from autistic disorder.