The advance of Internet technology worldwide has contributed to the growing impacts of online marketing of ecotourism destinations. Despite much discussion devoted to defining ecotourism conceptually, knowledge regarding how ecotourism is actually practiced and how it is marketed through the Internet is still lacking. The purpose of this study was to address these issues by exploring how ecotourism is marketed through the Internet. A sample was selected from ecolodge operators listed on the website of The International Ecotourism Society. Content analysis was used to examine the online marketing information of these ecolodges. The study findings suggest that ecolodge operators sampled in this study provided a variety of ecotourism products to meet the diverse interests of the ecotourist market. The online marketing messages of these ecolodges also indicated that most of them only partially aligned with ecotourism principles. Recommendations are made regarding social marketing and ecolabelling for online ecotourism marketing to better shape tourist expectations, attitudes and behaviours in ways that support the sustainable practices professed as ecotourism.