The present study investigated the key determinants of Chinese students' academic success in terms of GPA and the number of credit hours earned in Korean Universities. The determinants investigated included gender, age, prior academic performance, academic self-efficacy, the TOPIK score, self-perceived Korean and English proficiency, and the previous length of Korean and English study. This study specifically focused on three research questions concerning the prediction of Chinese students' academic success in Korean universities, the additional contribution of Korean and English language proficiency, and the examination of prediction patterns for undergraduate and graduate students. A questionnaire was issued and collected from 138 undergraduate and 63 graduate Chinese students studying in 27 different Korean universities. The questionnaire consisted of four sections: demographic information, academic background, language proficiency and psychological factors. Correlation and multiple regression analyses were conducted to address the proposed research questions. The findings demonstrated that traditional factors, including gender and prior academic performance, were effective predictors of academic success. However, academic self-efficacy did not play an influential role in participants' academic success. Language proficiency had a moderate effect on Chinese students' academic success, which is consistent with previous studies that reported a positive statistically significant relationship between language proficiency and academic success. The different natures of undergraduate and graduate studies determined that the predictors of undergraduate and graduate students' academic success were different. The present study addressed the research gap by integrating theoretical constructs from both psychology and language education, and also by exploring the relationships between language proficiency and academic success in a less researched test, TOPIK, and in two second languages, Korean and English, at the same time. The findings of this study contribute to the overall understanding of international students' academic success, in particular the success of Chinese students studying in Korean universities.Keywords: Test of Proficiency in Korean (TOPIK); Language proficiency; Academic success; Academic self-efficacy; Chinese students Current research on international students has focused on the relationship between language proficiency and academic success. Academic success is typically measured by Grade Point Average (GPA) whereas language proficiency is most often evaluated using international tests such as the Test of English as a Foreign Language (TOEFL) and the International English Language Testing System (IELTS). As more and more