The dugong is an herbivorous marine mammal species, being vulnerable to extinction throughout its range in the Indo-Pacific region. This paper used the choice experiment method to elicit the non-use value, or the non-users’ willingness to pay (WTP) for conserving the dugongs in Thailand. A face-to-face interview was used to obtain data from 300 residents in five selected districts of Bangkok. The results show that the average WTP for the most preferred dugong conservation scheme (a marker buoy system, recreating habitats, and slowing down the population decline) was 4,382 Thai Baht (USD122) annually per household. Significantly, developing the marker buoy system to identify dugong habitats was the most valued by the general public. However, the respondents were not willing to pay for educating local fishers about the conservation of dugongs. Our results implies that a conservation policy should concentrate on the participation of key fishers in dugong protection projects using incentive measures. We also suggest the government to create protected areas as dugong sanctuaries that consistently support the remaining dugong population.