The practice of education has changed during the COVID-19 pandemic. Educators such as teachers and pre-service teachers have to change their teaching practice that was previously conducted directly inside the classroom into an online teaching practice. In order to make sure the online teaching practice goes well, educators need to have a strong belief about their capabilities. This belief is called self-efficacy. This research objectives of this research are to find out the level of pre-service English teachers' self-efficacy during their online teaching practice and to identify the sources of self-efficacy that had an influence on them. This research uses descriptive qualitative as a research design. This research involved ten pre-service English teachers who already finished their teaching practice. In order to gain a description of how the pre-service English teachers performed their teaching practice, the research's data was gathered using questionnaires and interviews. The finding of the research shows that pre-service English teachers have a high level of self-efficacy during their online teaching practice. The pre-service English teachers show a high level in three indicators of self-efficacy and a low level in one indicator. Furthermore, the finding of the research also shows that all the sources of self-efficacy had an influence on them. This research can be beneficial for teacher educators. This research can provide teacher educators with information to develop a lesson that can prepare the pre-service teachers before their teaching practice and further improve the self-efficacy of pre-service teachers.