With the world of fast-developing technology today, consumers have to face with various innovation alternatives in their lives. One of the service technologies recently offered is QR code payment application. In the People Republic of China, this QR code application has been widely used and this QR code instruemnt seems to turn China into cashless society. In Thailand, this service technology was lately launched by a few commercial banks, and it remain new to Thai users. This study adpoted a widely acceptable technology adoption model and extended it with the additional factor, perceived credibility, and a moderator, perceived self-efficacy in order to investigate the factors which may affect users' adoption and usage of QR code payment application. The data were collected in Thailand via online survey with the sample size of 275. The findings show that perceived usefulness is very influential factor for QR code application adoption whereas perceived ease of use and perceived credibility are less important. The proposed modified TAM model was examined and found that perceived usefulness, perceived ease of use, and perceived credibiity significantly positvely affected the behavioral intention to use QR code application. Furthermore, the perceived self-efficacy was found to have a significantly moderating effect on the relationship between perceived ease of use and behavioral intention to use. This provides and incremental understanding of the impact of self-efficacy construct for the technology adoption and usage literature.