This paper is aimed at discussing the nursing experiences of a teenager during the radiotherapy for osteogenic sarcoma. Throughout the period of nursing practice, the author used Roy's adaptation model to collect the data regarding the patient's physical, psychological and social responding behavior. Our data showed that, the patient presented some symptoms and potential dangers such as diarrhea, pain, imbalanced mutrition: less than body requirements, risk for infection, risk for deficient fluid volume, risk for impaired skin integrity, and disturbed body image, all of which may cause nursing problems. In light of the importance of peer relationship among teenagers, the personal relationship was established between nurses and the patient. The patient was not only provided with physical content but also taught self-caring skills which included the prevention of infection, prevention of the deficient fluid volume, the maintenance of the integrity of skin. In addition, the patient was assisted in his using of resources to restore the mental and physical self-imaging. The purpose of this paper is to share the experiences with nursing personnel who might encounter similar cases in the future.