Using direct sunlight for the post-harvest drying process is easy and cheap for most small farmers in rural areas in developing areas. This method has weaknesses, namely the emergence of musculoskeletal complaints, fatigue, and additional workload due to unnatural working postures and exposure to hot sun on workers. Apart from that, the drying temperature is not optimal because it relies only on environmental temperature and is weather-dependent. As an alternative, a dryer can be used by applying ergo-mechanical principles. Ergo-mechanical is used to overcome work problems in the drying process and produce an ergonomic mechanical structure, thereby creating health, safety, and work sustainability. Ergo-mechanical applications are based on workers' participation as users, known as participatory principles. Participatory, as part of applying ergonomics concepts, aims to create harmony between work tools and workers. Ergo-mechanical is applied in designing dryers through ergonomic and mechanical studies to produce dryers that suit their needs and avoid causing new problems for small farmers. To design dryers, ergonomic studies were carried out using anthropometric data of workers as users. Meanwhile, mechanical studies were carried out by applying the principle of heat transfer between two fluids, namely fuel and environmental air.