The main purpose of this research paper is to explore and assess the challenges and difficulties facing L2 learners of Arabic due to the diglossic situation in the Arab world and whether to learn both codes, standard and dialectal or one of them. The study also tries to understand the nature of the awareness and motivation of L2 learners about the Arabic diglossic situation in Iraq. Therefore, the procedure followed to achieve this assignment highly based on, and thoroughly examined, enormous references, verified and analyzed some statistical procedures previously used by other scholars related to diglossia along with the debate sessions held with some native teachers of Arabic as a Foreign language who have taught and still teaching this language to non-native speakers. The originality of the study lies in the invaluable information gained, through the discussion sessions as well as interviews held with these well-experienced teachers and students which definitely added a significant depth to the findings of this study. Further, the study has presented and discussed the perspectives of some scholars, who are prominent in the field of sociolinguistics, as well. This really reflects the practical objective implications of the study teachers. Eventually, the findings reveal that teaching/learning Arabic as a foreign language is not an easy task due to the diglossic situation in the Arab World.