There has been a growing use of language tests to determine student eligibility for different levels of college English courses in China. The study examined an online EFL placement test with a focus on its construct and predictive validity. A multi-phase mixed-methods approach was employed to collect data. For the first phase of the study, we analyzed the relationship between placement test scores of 1,095 freshmen and their final grades, taking into consideration students’ disciplines. For the second phase, a sample of 12 students at different levels from different faculties were invited to complete think-aloud protocols during a retest to explore the sub-skills of each sub-section including listening, reading and language use. Followed-up interviews with both the students and their instructors were also carried out to investigate their perceptions of the placement test and the use of test results. Findings showed that students entering the university English courses on the basis of the placement test scores feel prepared and generally regard the test as an effective means of preparation for their English studies in the university.