The role of native language in teaching a second or foreign language has always been controversial in the language teaching. In this study the role of native languages of Kurdish and Persian in the success of English learning has been studied. Two groups of Kurdish and Persian speakers were selected to function as the participants of the study. A reading comprehension course was taught during a university semester in University of Kurdistan. For Kurdish speakers every kind of explanations and instruction was done in Kurdish and the same procedure was also applied to Persian speakers through the medium of Persian. The results of the study showed that the Kurdish native speakers outperformed the Persian speakers in achievement in reading comprehension of English. The results were interpreted as the closeness of Kurdish and English language systems in some regards better than that of the Persian language.
