The Philippine duck (Anas luzonica) is a vulnerable species, endemic to the Philippines. The need of local people for food and land has led to the endangerment of the Philippine duck populations through illegal hunting and the conversion of wetlands to aquaculture and farmland. This study was conducted to determine the willingness to pay (WTP) of residents (n = 500) in Maguindanao provinces for the conservation of the Philippine duck and the effects of conservation attitude and knowledge toward the Philippine duck, as well as sociodemographic characteristics, on WTP. The mean annual WTP for Philippine duck conservation was USD 0.60, and the total estimated annual amount that could be collected was USD 134 thousand when projected based on the number of households in the Maguindanao provinces. A positive conservation attitude and high knowledge increased the WTP for Philippine duck conservation. Females, pet owners, and those with higher income pledged a higher WTP than males, non-pet owners, and those with lower income. This study revealed that local residents are supportive of the conservation of the vulnerable duck populations by paying a considerable amount. These results are critical for designing and implementing outreach programs for increasing awareness and the acquisition of funds urgently needed for the protection and conservation of the remaining Philippine duck population in the area.