The present study aims at considering the linguistic influence of official standard Persian language on idiom comprehension focusing on parts of body comprehension of Kurdish EFL learners. Iranian Kurds have studied in schools in which the language spoken or written has been different from their mother tongue. The present study is based on data from 92 EFL learners whom Kurdish is their first language and Persian is their second language. The participants were females and males studying English as a foreign language at two universities; Azad and Kurdistan universities of Sanandaj in Iran. They were exposed to three idiom tests and a questionnaire. English language proficiency, educational background, gender, age and type of university were controlled. They outperformed their second language idioms. The findings show that transfer from L1 was not always dominant in non-native comprehension due to lack of academic instruction of L1. The role of exposure and academic instruction as factors were found to affect transfer from L2 in L3 comprehension while participants were more exposed to L2 at school and via media. The study confirmed our assumption that Kurd learners’ L2 has a significant role in transfer of concepts to L3.