The study determined the economic value of the proposed liquid organic fertilizer (LOF) project in the Vietnamese Mekong Delta through the estimation of farmers’ willingness to pay using the approach of the double-bounded dichotomous choice contingent valuation model (DBDC CVM). The results showed that the majority of farmers supported and agreed to buy LOF with a willingness to pay or a price of around 169,000 VND ($7.44) per ton. Farmers who used to apply organic fertilizers before or consider the use of biomass fertilizer as safe are more likely to pay for the proposed LOF.