This study aims to explore how the degree of education related to information systems and the Internet literacy affect perceived security risk and how these three variables affect online transaction intention based on the Technology Acceptance Model (TAM). Since using smartphone to purchase necessary products is increasing, the study provided two different cases of using the existing Internet and smartphone to buy products. As a result of an empirical test, the degree of information system education, internet literacy, and perceived security risk had significant effects on online transaction intention mediating perceived usefulness and perceived ease of use. Unlike the expectation, the more people have education related to information systems, the more they have knowledge about hacking or cases of privacy infringement, leading to even more concerns about security, thereby believing the Internet transactions require much effort. The more the education about information system, the more we have concerns about security; therefore, perceived security risk have a positive(+) effect on perceived usefulness not a negative(-) effect. Lastly, while the degree of education related to information systems has relations with the recognition of the usefulness of the Internet transaction, the study showed that there are no relations of recognizing the usefulness and the ease of use of smartphone.