The Health Impact Assessment of Map Ta Phud Industrial Development and Its Vicinity is a retrospective case study and successfully carried out with support of the Research and Development Program on Healthy Public Policy and Health Impact Assessment (HPP-HIA) under the Health Systems Research Institute. The study is also done in response to the Program’s approaches towards the health systems reform. Industrialization of Map Ta Phud has been carried out based on the policy to promote the Eastern Seaboard program since early 1980’s. Map Ta Phud is assigned to serve heavy industries of petrochemical, oil and gas refinement, iron and steel for the period of 50 years.  Industrialization here stemmed from hopes and dreams that economic propensities were being brought to the country, and that it would uplift Thailand to the status of a Newly Industrialized Country, in particular promising exploitation of natural gas.  Map Ta Phud was touted as the most modern industrial estate in the making. Public was promised that with its high standard of management and control, there would be no pollution problems. However, in the last two decades, accumulated pollution and environmental problems as well as mysterious diseases have begun to emerge as very much linked to each other, and hugely affected small people in the area. At present Map Ta Phud People suffer hard the air pollution especially the bad smell while Rayong province boasts the highest number of patients suffering from respiratory diseases. The province is also known as having one of the most highest numbers of AIDS infected people and AIDS-related deaths as well as a great number of mentally ill patients and commit suicide cases. Similarly, the number of industrial incidents and accidents on roads is dramatic due to rapidly increasing chemical use and  transports. Drastic changes in the exploitation and quality of natural resources and production of rural sector are obviously akin to the uprooting of the way of life of individuals, families and communities which directly affects to their livelihood.This study, therefore, put on exploring impacts at Map Ta Phud in various forms, in particular through the issue of “health” under a much broader definition than the conventional one. According to the essence of the drafted National Health Act, “health” is defined as the state of human integrated well-being in four aspects of physical, mental, social and spiritual health.  Consequently, the outcomes revealed in this paper are rather vogue and pioneering, as there has been none of such study on industrialization with this particular focus.  In addition, this paper also applies the WHO’s health and environment analytical  framework (or DPSEEA model) to  analyze the causes and effects of industrial development at Map Ta Phud. The framework divides the analytical process into five levels of Driving force, Pressure, State, Exposure, Effects and Actions. Based on the process, each specific development programs will be recognized as the driving force of the overall potential health impacts and risks. This driving force can lead to increasing in environmental and social pressures. Such pressures might cause drastic changes in the state of environmental and social quality,  after which it leads to  exposure to the industrial pollution and social problems and finally ends up with various forms of health effects. Apart from the WHO’s model, the conceptual framework of healthy public policy process is also partially applied in responding to some complicated aspects of the existing problems as well as to propose proactive approaches at different levels to improve those health effects.