<p>Online business makes it easy for buying and selling transactions but in Indonesia the customer trust still low. Eventhough there are government regulation  that cover the risk of online transaction in order to minimalize online bussines fraud. Therefore this study aims to research about factors influencing customer trust. Various factors can affect the trust of online transactions. This research focused on the electronik service quality (e-service quality), relationship quality and customer trust. Data collection was gathered from top five customer e-commerce in Indonesia (275 respondents). Statistical analysis was using Partial Least Square (PLS). The results show that the mediation effect of the relationship quality is discussed.</p>