the presence and severity of lung disease by interpreting measurements of pulmonary function tests, NEOMYCIN helps physicians diagnose and treat patients with meningitis and similar diseases, MED1 helps physicians diagnose diseases associated with chest pain. GUIDON for instruct in bacterial infections, and HEME helps physicians diagnose hematologic diseases. From these researches, we found that they benefit to public health. However the medical and public health in Thailand is based on the assumption that fundamental of public health is the heart of public health development. The important goal is population which can take care themselves, and they can learn and understand self-care, disease protection, and healing. However, there are not enough staffs of health for giving advice to population so this is an important problem for country development. From study we found almost diagnosis that is performed in history taking to chief complaint and symptoms. So this research presents design and development of the medical knowledge-based system. It is an alternative way to support public health of country, and this system help to create the medical knowledge-based system