The tourism industry has played an important role in the Indonesian economy. Nowadays, many online travel agencies have started emerging and growing all over the world, including Indonesia. In Indonesia, Traveloka ranked first as the most popular online travel agent. This research aims to determine the relationship between brand image, brand trust, service quality, and customer satisfaction toward brand loyalty of online travel agencies in Indonesia, using Traveloka as a research object. In this research, brand image, brand trust, and service quality act as an independent variable, customer satisfaction as an intermediate variable, and brand loyalty as a dependent variable. This research uses a quantitative paradigm and descriptive research design. The subject of this research is individuals who have used or purchased the services of Traveloka. The data collection method conducted in this research is through administering a questionnaire, that is distributed electronically through Google Form. This research uses non probability, convenience sampling. Pre-test is conducted by administering the questionnaire to 30 first respondents and actual research to 153 respondents. Data were analyzed using SmartPLS. From 4 hypotheses being tested, 4 are accepted. In other words, all hypotheses in this research are accepted The data analysis results shown in this research concluded that there is a positive influence between brand image, brand trust, service quality, and customer satisfaction toward the brand loyalty of Traveloka online travel agent.