The purpose of this case study described a nursing experience which applied the Roy's adaptation model to take care of an elementary school child with type Ⅰ Diabetes Mellitus. The caring period of time was from March 21st to March 28th, 2008. The Roy's adaptation model was used as an assessment basis through the ways of observations, interviews, physical examinations, and nursing care to collect data. The primary health problems were identified including deficient knowledge, anxiety, and ineffective coping behavior. The nursing process was embedded with therapeutic games involving knowledge and skills of adequate blood glucose controls. Furthermore, the child was encouraged to express her emotion with the help of the author's attitudes of sympathies, acceptances, and supports to promote and achieve the goal of adaptation to maintain her health. This nursing experience can be shared with pediatric nurses to take care of similar cases clinically.