Background and Objective: Diabetes is an incurable disease among the elderly. It is estimated that it affects the quality of life, and non-pharmacological and psychological therapies can help reduce the problems of the elderly with diabetes. The objective of this study was to compare the effectiveness of laughter therapy and solution-based therapy on hopefulness, meaningfulness, self-compassion, and hemoglobin A1C elderly patients with type 2 diabetes. Materials and Methods: The present study was quasi-experimental with pretest-posttest, follow-up, and control group. The statistical population of the study included elderly patients 60-75 years old with type 2 diabetes referred to the Iranian Diabetes Association in Tehran. Among them, 54 were randomly selected and replaced in three groups: laughter therapy, solution therapy, and control group. Data were obtained by self-compassion questionnaire, hopefulness scale, meaningfulness questionnaire, and glycated hemoglobin test. Before the beginning of the sessions, the pretest was administered for all three groups. After two months, the posttest was administered. In the first experimental group, laughter therapy, in the second experimental solution-centered intervention, and in the control group, no intervention was done. Glycated hemoglobin test was completed again two months after the end of the training in order to follow up and evaluate the sustainability of treatment effects. Data were analyzed by repeated measure ANOVA and SPSS software. Results: The mean (SD) of self-compassion in the laughter group increased from 67. 5 (5. 2) at pretest to 85. 8 (6. 2) at posttest and 86. 2 (6. 1) at the end of the follow-up period (P<0. 001) and increased in solution-based therapy group from 69. 2 (4. 7) in pretest to 81. 3 (8. 3) in posttest and 81. 7 (8. 4) at the end of the follow-up period (P<0. 001). The mean (SD) of meaningfulness in the laughter group increased from 43. 9 (6. 2) at pretest to 50. 3 (6. 8) at posttest and 50. 7 (6. 5) at the end of the follow-up period (P<0. 001). It increased in the solution-based therapy group, from 44. 8 (6. 7) at pretest to 49. 5 (7. 9) at posttest and 49. 8 (7. 7) at the end of the follow-up period (P <0. 001). The mean (SD) of hopefulness in the laughter group increased from 40. 3 (8. 1) at pretest to 45. 6 (8. 1) at posttest and 46. 1 (7. 7) at the end of the follow-up period (P<0. 001) and increased in solution-based therapy from 40. 2 (7. 9) at pretest to 43. 7 (8. 1) at posttest and 43. 7 (7. 7) at the end of the follow-up period (P<0. 001). The mean (SD) of hemoglobin A1C in the laughter group decreased from 7. 3 (1. 6) at pretest to 6. 4 (1. 1) at posttest and 6. 3 (0. 9) at the end of the follow-up period. (P<0. 001). Moreover, it decreased in the solution-based therapy, from 7. 2 (1. 1) at pretest to 6. 6 (1. 1) at posttest and 6. 6 (1. 1) at the end of the follow-up period (P<0. 001). In the control group, there was no significant difference in mean (SD) self-compassion, hopefulness, meaningfulness, and A1C hemoglobin levels in pretest, posttest, and follow up. A comparison of two treatments showed that laughter therapy was more effective in self-compassion and meaningfulness in the posttest period than solution-based therapy (P<0. 001). Conclusion: The study showed that both laughter therapy and solution-based therapy led to increased hopefulness, self-compassion, and reduced hyperglycemia. Laughter therapy was more effective than solution-based therapy in enhancing self-compassion and meaningfulness in patients with diabetes. However, there was no difference between hope and hyperglycemia in two therapy methods.