The COVID-19 pandemic has led to the temporary closure of schools around the world. Due to the sudden and complete transition to online instruction, teachers were faced with various challenges. The assessment of student performance is one of the integrative segments of remote teaching. Therefore, the aim of this study was to examine the relationship between teachers' perceptions of online assessment and different facets of self-efficacy. The study involved 147 primary and secondary school teachers who completed an online survey. The results of multiple regression analysis revealed significant effects of teachers' ICT self-efficacy and teachers' self-efficacy concerning student engagement on the perception of some aspects of online assessment. On the other hand, teacher self-efficacy for instructional strategies was not a relevant predictor. In light of the obtained results, suggestions for future research were discussed.