This study attempted to compare the speech act of main components of complaint strategies in English and Persian in varying situations in two contextual variables, namely, social power (P) and social distance (D). The performance of Iranian EFL learners was also investigated to see how they performed complaints in the target language. A Discourse Completion Test (DCT), composed of six open-ended items, was administered to 24 Iranian students majoring in English Language and Literature at Shiraz University, who were selected based on their score on TOEFL proficiency test (2004) and 16 Australian English native speakers. Data collected through the DCT, were coded and analysed based on taxonomy of complaints developed by Rinnert and Nogami (2006). The focus of the study was on the main component taxonomy. Chi-square tests were conducted to compare the performance of the groups. The results of chi-square for teacher situation showed that the Australian English native speakers (AE) significantly used an initiator more frequently than the Persian EFL learners (PE) and the Persian native speakers (PP). In the case of the academic advisor situation, the AE speakers significantly employed complaints more frequently than the PP. On the part of student situation, the AE speakers started the conversation with a complaint more frequently than the PP speakers. The participants in the PE group significantly used a request more frequently than the AE, but the AE and PP speakers used this semantic formula exactly equally. In the case of other situations, the results of chi-square revealed no significant differences in the frequencies of using complaint patterns between the groups. The performance of Iranian EFL learners showed that they sometimes significantly diverged from their English counterparts. It was concluded that other factors, along with negative transfer, were responsible for such a divergence.