This study examines how English as a foreign language (EFL) students in Korean colleges use contrastive connectors in their academic writing. It analyzes the second-language (L2) writing samples of Korean EFL writers (non-native speakers: NNS), focusing on the frequency and positional distribution of contrastive connectors such as but and however, and compares them with a corpus of native English writers (native speakers: NS). Findings show that NNS tended to use, but more and with a simpler and shorter clause, but no remarkable difference can be observed in the use of however. In addition, usage patterns show differences among different corpora, especially in the case of but when it is located initially in the sentence. Finally, the paper concludes with some pedagogical implications. (Kookmin University)