Prior research on the relationship between International Baccalaureate Diploma Program (IBDP) scores and the university entrance exam scores is limited and varied to a great extent due to the conflicting results in the literature. This study investigates whether there is any relationship between the students’ achievement performance in IBDP and university entrance exam performance. The study revealed that there is no statistically significant correlation between IBDP scores and university entrance exam rank orders. Furthermore, the study showed that the IBDP scores cannot be taken into account as a strong predictor for university entrance exam performance.