The disaster could be classified into 2 major types, ‘natural disaster' and ‘environmental disaster'. The environmental disaster is thought to be classified into ‘disaster from environment destruction', ‘disaster from environment pollution', and ‘disaster from environment inflexibility'. Most of enormous disasters can be considered to be composed of natural disaster and environmental disaster. Bangladesh is one of the serious poor countries in the world, and it has been suffering many kinds of disasters, such as cyclones, floods, droughts, arsenic contaminated drinking water and infectious diseases. In this study, arsenic contamination of drinking water in Bangladesh is focused on, which can be regarded as a typical combination of natural disaster and environmental disaster. In Bangladesh, arsenic contamination is found in the ground water from wells which were built with assistance of other countries to reduce the risk of infectious diseases. After the arsenic contamination was revealed, the measures for arsenic contamination have been provided by other countries and international organizations. However, it becomes clear that Bangladesh people accept few of them. Why ? After 3 investigations in this study, the reason could be concluded; temporal proposals and provisions of techniques to reduce the risk of drinking water contamination have been promoted by other countries without consideration of local people's traditional ways of life so that they became reluctant to be accustomed to those techniques. From above recognitions, the purpose of this study is aimed at analyzing the relationship between arsenic contamination and social environment in Bangladesh. First, interview with Bangladesh people was carried out with corporation of local NGO. Second, the factors for satisfaction with drinking water are analyzed. Third, the unhappiness function is set up. Finally, the latent factors of incredulity with technical supports from other countries are disclosed. JEL classification: I18, I31, I38