It is fundamental for language teachers to assess their students' performance. Therefore, they should be familiar with various forms of assessments because teaching and assessing languages are closely related and have a great deal to do with one another. This study examined EFL preservice teachers' perceptions of assessment literacy at a medium-sized university in South Korea, employing a survey questionnaire of self-perceived language assessment. The survey results reveal significant variability in the confidence levels of EFL preservice teachers across six domains of assessment literacy, with the highest confidence in preventing cheating and the lowest in constructing tests for advanced learners. Challenges in communicating assessment results, particularly with parents, indicate a need for professional development in communication strategies. While ethical practices and digital assessment literacy show strong commitment and proficiency, areas like avoiding "teaching to the test" and designing online tests require further training to ensure comprehensive assessment capabilities. Such an investigation in this study will assist in spreading the significance of assessment literacy and its results on teaching and learning. The implication of the study is expected to improve the policies and practices in the field of education.