Xuan Thuy National Park, a special nature reserve with mangrove swamps located in the Red River Delta in North Vietnam, plays an important role in combating coastal erosion and provides a habitat for many endangered bird species. This study applied double-bounded dichotomous choice contingent valuation method to directly estimate how much locals are willing to pay for mangrove conservation at Xuan Thuy National Park. In particular, the technique was used to provide better assess to the non-use value of biodiversity and ecosystem support of mangroves. Survey respondents from 350 households in the buffer zone were presented with a hypothetical scenario describing a policy that quantifies the environmental change to be achieved by 2030, and specifying a lump sum payment. Non-parametric estimate of mean WTP was found at 511,090 VND per household (22.03 USD) whereas parametric estimate of mean WTP derived from the log-logistic specification was found at 619,908 VND (26.73 USD) per household. Awareness of mangrove benefit and interest in conservation activities have a positive impact on WTP responses, in addition to income. The findings will help policy-makers adopt sound environmental policies and advise locals on the importance of protecting the mangroves which in turn protect their livelihoods.