The purpose of study was to determine the effect of a self-help group program on the quality of life among type 2 diabetic patients. The study subjects were type 2 diabetic patients attending one of six studied health centers or a community hospital in Saraburi Province, Thailand. At each health center/hospital, the patients were randomly allocated into the intervention group attending the self-help group program or the control group receiving diabetic services. Information was collected from September 2007 to April 2008 using a structured questionnaire with interview technique at baseline, 12 and 24 weeks. One hundred forty-six patients completed the program. Five self-help group programs carried out for 16 weeks gave instruction regarding building-up good relationships, improvement of knowledge about diabetes and skills for dietary control, skills in physical exercise, improvement of group structure, improvement of training skills for group leaders, self-monitoring, motivation in self-care activities and sharing experiences among group members. Descriptive statistics were used to provide basic information regarding the two groups. For analytical purposes the chi-square test and t-test were applied. The majority (77.4 %) of study participants were females. Most patients were either ≥ 50 years old (52%) or 40-49 years old (37%). The intervention resulted in significantly higher scores in quality of life compared to controls at 12 and 24 weeks (p < 0.05). The findings indicate the program is effective for improving perceived quality of life. The program focused on enhancement of experience sharing among group members and participation in problem-solving. We recommend implementing this program for diabetic patients and patients with other chronic diseases at primary health care level.