The paper aims to identify factors affecting sustainable ecotourism in Vietnam, including the mediating role of tourist satisfaction and attractive destinations. The valid quantitative data were collected from a survey of 515 domestic tourists who have traveled to ecotourism areas in 5 selected areas in Vietnam, including Ca Mau Province, Can Tho City, Ho Chi Minh City, Binh Dinh Province, and Dong Nai Province. To test research hypotheses, data were analyzed using AMOS 24.0 and structural equation modeling (SEM). Research results show that tourist satisfaction strongly affects sustainable ecotourism (β = 0.341), followed by attractive destinations (β = 0.175) and environmental awareness (β = 0.147). In contrast, tourism management policy does not affect sustainable ecotourism. Besides, tourism management policy has the strongest influence on attractive destinations (β = 0.393), followed by the natural environment (β = 0.129), culture and society (β = 0.082), but infrastructure does not affect attractive destinations. Research results also show that the strongest influential determinant of tourist satisfaction is infrastructure (β = 0.448), followed by culture and society (β = 0.180), the natural environment (β = 0.150), and tourism management policy (β = 0.136).