Nowadays, eTourism has a very promising development in Indonesia. This triggers the growth of various sites that provide a marketplace to buy and sell open-trip. Hence, this study aims to identify factors that influence tourists’ intention in ordering open-trip package through open-trip marketplace sites using the approach of Task-Technology Fit theory. This study uses quantitative methods and uses questionnaires for data collection. The questionnaires obtained 57 respondents who booked through an open-trip marketplace sites. The collected data is then analyzed using Partial Least Square Structural Equational Modeling (PLS-SEM). This study found that Task-Technology Fit significantly affects tourists’ intention to buy open-trip from open-trip marketplace sites. Then, this study showed that technology characteristics affects Task-Technology Fit, and website quality is a factor that influences technology characteristics. Moreover, this study also found that task significance is a factor that significantly affects task characteristics.