Tourism activities generally put more emphasis on the provision of maximum economic benefit. Less attention is given to its environmental impact and this can lead to disruption in the condition of the physical environment. If this continues, then, in the long run, the physical environment in the region will be no longer attractive and be harmful to the tourism sector.To achieve sustainable tourism, harmonization of tourism and conservation activities would be essential. One potential effort to be implemented is through the Payment for Ecosystem Services (PES) program. By taking a case study of marine tourism in the Gili Matra in West Nusa Tenggara Province, this study analyses the potential for achieving sustainable tourism through harmonizing marine tourism activities and conservation of coral reefs and other marine biotas, through the PES scheme. Using the contingent valuation method (CVM), this study seeks tourism entrepreneurs' willingness to contribute to funding the PES program. The study found that tourism entrepreneurs are willing to pay an average of Rp 42,200 (equal to 2.86 USD) per month for the PES fund. The level of revenue, length of business, and impact of coral on the respondent's economy influence the willingness and the amount to pay.