Fethiye District is an important tourism center that possesses a lot of natural, historical and cultural appealing such as The Butterfly Valley, Dead Sea, Babadağ, Kayaköy, Telmessos, Hidden City and Caliş Beach. This district which is an important destination for sea tourism has a great potential in terms of ecotourism. This study aims to measure the perceptions and expectations of the service quality of the tourists that visit The Butterfly Valley, where possesses an ecotourism potential, via ECOSERV method and find out service quality. A survey has been applied to 151 foreign and local tourists in this study. The study has been evaluated under six dimensions in EKOSERV service quality measuring model in terms of tangibles, assurance, reliability, responsiveness, eco-tangibles and empathy.