Aim The objective of this study was to evaluate the effects of a comprehensive overweight intervention program, which utilizes hot bathing, on overweight, community‐dwelling middle‐aged and older adults in a randomized controlled trial. Methods The program was carried out in a hot bath facility and included 66 community‐dwelling middle‐aged and older Japanese adults (mean age 61.6 years, SD 7.5, 77.3% were women). The participants were randomly assigned to an exercise, diet and hot bathing intervention group (group A), exercise and diet intervention group (group B), a hot‐bathing intervention group (group C) and a control group (group D). The participants in groups A and B participated in a comprehensive intervention program (including exercise and diet classes) twice a week for 3 months, and groups A and C had hot bathing. Results After 3 months, the participants in group A showed a reduction in weight, abdominal circumference, body mass index and body fat percentage compared with the other intervention groups. And the lower extremity function (i.e. walking speed) had greater improvement in the participants in groups A and B compared with groups C and D. In group C, in which only hot bathing was the intervention, there were no significant improvements in measurement items. Conclusions Our study provides preliminary evidence that a comprehensive intervention program, including hot bathing, is useful for community residents with a tendency toward overweight. Geriatr Gerontol Int 2013; 13: 638–645.