Successful biodiversity conservation is closely linked to the support received from society. Therefore, a better understanding of public preferences for conservation activities facilitates successful conservation efforts. The objective of the study is to determine the preferences of tourists and local residents regarding the proposed conservation program of the northern yellow-cheeked gibbon (Nomascus annamensis) and its economic value in the Bach Ma National Park, as well as to examine the factors that determine their willingness to pay (WTP) for the gibbon conservation. The WTP was estimated with the dichotomous choice contingent valuation method, and data were collected using face-to-face interviews with 710 participations, including 352 Vietnamese tourists and 358 local residents. The logistic regression model was applied to predict the probability of WTP for the program. A number of factors were found to be significant predictors of WTP that included bid level, visit, awareness, knowledge, distance, family size, and education. The mean WTP amount was estimated at about $US3.81/tourist and $US 2.93/household for one-time support of the gibbon conservation program. A significant difference was also found between the tourists and local residents in terms of the estimated WTP. Our findings suggest that there is a strong public support within Vietnamese society for the conservation of gibbons, which should be considered in the design of social policies for biodiversity conservation and natural resource management.