Objectives: The purpose of this study is to develop a program of group psychotherapy named "the promotion of hope program (PHP)" that will provide effective emotional support for cancer patients. Methods: In order to develop a group counseling program for cancer patients, this study utilized reality therapy based on Oriental medicine theory which is the mind affect the body. We established four steps for making positive changes to individual behavior: creating soil for hope, watering hope, sprouting hope, and the blossoming flower of hope. To verify the effectiveness of the program, we conducted a comparative clinical trial. Patients were divided into two groups by unrestricted randomization: the intervention group (n=20) and the control group (n=17). The members of each group did not exceed seven patients. We divided the trial period into three sections. The intervention group received group psychotherapy twice a week for 4 weeks. The control group watched hope-related videos and talked about members for two hours each week for four weeks. We evaluated the scale of anxiety and depression, self-esteem, and hope, both before and after the examination. Results: PHP decreased the level of anxiety and depression in the intervention group (1.21 vs. 0.75, p<0.01). PHP also improved the level of both self esteem (2.80 vs. 3.34, p<0.01) and hope (2.69 vs. 3.23, p<0.01). In contrast, the control group showed no interval change at any point in time. Conclusion: Following the above results, PHP can be seen as an effective program for helping cancer patients to increase positive emotions and behaviors while reducing negative thoughts.