Culture is an inseparable part of a language. In other words, mastering a language and being able to communicate through it inevitably entails integrating with the culture
of the speakers of that language which is the reflection of people's identity. The aim of the present study was designing a model of Iranian cultural identity. Initially, to select a homogeneous sample of learners at the advanced level, ۳۰۰ language learners at the advanced level took TOEFL and ۱۸۰ learners were chosen as the participants of the study. The cultural identity model was designed by the use of interviews and literature review to come up with main components of cultural identity. Afterwards, participants were interviewed about their identity and four components comprising Iranian cultural identity were identified. The results of the factors analysis showed that raw data converged to a pattern with four components which fit the hypothesized model of cultural identity. Then, the cultural identity questionnaire was given to participants. The results of statistical analyses indicated that there was a significant negative relationship between cultural identity and language achievement of the participants.