This study aims to examine the relationship between trust, types of payment methods, perceived usefulness, and convenience to the people’s purchase intention and whether that affect people’s online shopping behavior in SMEs in Indonesia—types of payment methods. Data were collected from 205 respondents in Indonesia using purposive sampling. Path Analysis was used in this study, and the results showed that Perceived Usefulness has a strong, unidirectional positive influence and significant effects on the Purchase Intention of payment gateway users but is not significant to Online Shopping Behavior. Convenience variables have a strong, unidirectional positive influence and significantly affect Purchase Intention and Online Shopping Behavior of payment gateway users in Indonesia.