Diabetes is one the diseases that endangers most people’s health. Diabetes appears with disturbances in the metabolism of glucose, fat, and protein, which especially includes disruptions in producing and using insulin hormone that is necessary in glucose metabolism (
1). Iran is one of the countries that is at increased risk of diabetes, thus, 14% - 23% of Iranians 30-year-olds and above have diabetes or impaired glucose tolerance (IGT). Nearly 25% of IGT would get diabetes in the future (
2). The main causes are obesity and immobility, which are related with increased risk of type 2 diabetes (
3,
4). Stress has a negative effect on their body, psychological, and also endangers their mental health (
5). In addition to stress, depression (
6) and anxiety (
7) are respectively the most mental disorders in patients with diabetes. Considering the last studies in Yazd, the rate of depression in type 2 diabetic patients is 46%, where 70.4% are female and 48% male (
8). These psychological factors might have a significant impact on the mental well-being of patients with diabetes. Well-being is a psychological component that is considered as freshness and life satisfaction (
9). Mental well-being is a multidimensional structure, which is marked with social, mental, and physical freshness (
10,
11). Today tendency to study psychological well-being as one of the therapeutic process in former decades was increased (
12). Positive psychotherapy is one of the approaches that engage scientists to consider well-being and mental health (
13). Therefore, positive psychotherapy movement emphasizes on positive features and potentials growth in a person. Hence, a group of psychologists used mental health instead of psychological well-being because they believed that this word brings more positive aspects to someone’s mind (
14,
15). Seligman believes that positive psychology is a new method in psychotherapy that pays attention to potentials, talent, and positive emotions (
16). Indeed, positive approach suggests therapists not only try to eliminate symptoms of an illness but also try to enhance patient’s quality of life. Hence most of psychologists use some interventions in their positive therapeutic method, which was based on patient’s thought, feeling, behavior, and positive cognition (
17). Positive psychotherapy focuses on increasing the level of well-being, happiness, and quality of life. It believes that increasing positive emotions can decrease mental pressures and shortages as well as have a positive effect on mental health (
18 -
20). The effectiveness of positive psychotherapy has been checked on different illnesses. For example, Seligman et al. (
15) reported that positive psychology tasks decreased depression symptoms for at least 6 months. Senf and Liau (
21) and Asgharipoor et al. (
22), showed that positive therapy is effective in treating mental features and can also increase happiness and decrease depression symptoms. The mechanism of blood sugar reduction in participants can be explained such that positive psychotherapy training with positive motivational techniques on hypothalamic-pituitary-adrenal axis reduces Cortisol in response to stress. On the other hand, improvement of anxiety can decrease catecholamine release and lead to better glycemic control in diabetic patients (
23). It seems that these trainings can lead to better control of diabetes by suppressing or reducing the levels of Cortisol secretion. Therefore, participating in positive training courses leads to the reconstruction of individual belief and cognition about diabetes. Up to now, there wasn’t any research that has been done in regards to the effectiveness of group positive psychotherapy on improving psychological health of patients with type 2 diabetes.