The study estimates impact of climate changes in clam culture in Giao Xuan commune, Giao Thuy district, Nam Dinh province - one of five communes in the buffer zone of Xuan Thuy National Park. The study estimates the losses due to climatic changing using the hazard risk assessment methodology of International Center for Geo-hazards (ICG). The method uses the natural hazards-based approach based on the uncertainty of climate change scenarios and the climate-related sensitiveness of clams in particular and bivalves in general. The analysis finds that sea surface temperature is the biggest factor affecting clam culture beside storms. By 2030, the clam production of Giao Xuan commune could reduce by about 26% compared to the current production, reduce by 36.5% in 2050 and 57.5% in 2090. The study reaffirms the importance of solutions to minimize the impacts of climate change on aquaculture in the North of Vietnam.