One of the major characteristics of diabetes is that the compliance to self-management considerably affects the prognosis of the disease. Therefore, the diabetes educator is required to evaluate the patients from a psychosocial aspect to gain a comprehensive understanding and enhance their ability to adapt self-management activities. From the perspective of "Person In Environment," psychosocial evaluation refers to the holistic understanding of the patient, including family relationships, emotional status, financial affordability, social background, problem-solving skills and coping ability. With the psychosocial evaluation, the diabetes educator can practically help the patients set their goals of self management, improve their behavior patterns and maximize their locus of control.