Mother tongue rhetoric transfer is unavoidable in ESL writings, especially for Iranian ESL learners, since Persian and English language is quite different. The paper discusses the negative transfer of mother tongue rhetoric in Iranian undergraduate ESL learners’ writings from the perspectives of choosing rhetorical structure in English and Persian writing. In this regard, 50 intermediate undergraduate Iranian students who are a bachelor in engineering fields at two private higher education institutions located in Malaysia, are selected as participants to give their opinion about which style they prefer to use for both English and Persian writing. Statistical analysis of the participants' performance indicates that Iranian undergraduate students use the same rhetorical pattern for their both Persian and English writing and there is no consideration regarding the knowledge of L1 and L2 differences. The results also state that above 70% of the participants prefer to give a general comment about the topic and encourage readers at the end of the writing in their English and Persian essays.