Increasing attention has been focused on promoting the physical and psychological health of non-farmers through farm activities such as home gardening and allotment gardening. In addition to these two farm activities, another farm activity — assisting with farm tasks — has been recently observed among non-farmers. Assuming that certain activities promote the health of non-farmers, specifically assisting with farm tasks near the home, allotment gardening, home gardening, walking, hiking, light physical exercise, home training with gymnastic equipment, and bowling, the preference for assisting with farm tasks compared to other farm and non-farm activities for health promotion was assessed among non-farmers in Chiba prefecture, Japan. Based on the best-worst scaling approach, assisting with farm tasks and allotment gardening were found to be the least and second-least preferred activities, respectively, while home gardening was found to be more preferred than these two farm activities. According to our results, decreasing farm task difficulty, reducing the travel cost of visiting a farmer, and asking non-farmers to only assist with tasks that can be conducted at their own pace could increase the non-farmers’ preference for assisting with farm tasks as a method of health promotion.