It has been observed that vocabulary constitute an essential factor in foreign language learning. Learners of English language need to have command of a wide range of complex lexical units which are prefabricated as chunks of arranged patterns of phrases and words. Biber, et al.(1999:991-992) define lexical bundles as '' recurrent expressions or sequences of three or more word forms that commonly go together in natural discourse''. They(ibid) add that ''lexical bundles can be regarded as building blocks that tend to be used frequently by different speakers in different situations''.They are retrieved and reprocessed as whole units which may not only enhance the accuracy and fluency of language, but also speed up language processing significantly. The present study deals with the investigation of the role of teaching lexical bundles in the development of Iraqi EFL proficiency in the Department of English, Faculty of Arts, University of Kufa. The most important purpose of lexical bundles is creating discourse coherence which helps students tocommunicate and practice language with effective and successful facilities. The study attempts to answer the following questions: 1) Is the use of lexical bundles necessary and effective in enhancing and developing of Iraqi EFL? 2) What is the difference between students who are unaware and unfamiliar with the use of lexical bundles and those who are familiar and able to identify them? The sample of the test consists of two types of questions (fill in the blanks 'production' and multiple choices 'recognition' ) and 40 students are selected randomly at the mentioned department. The participants are divided into two groups , each group with 20 students. The first group who are not aware how to use lexical bundles constructed the pre-test exam and the second group with 20 students done the post-test exam who are well constructed with the experience and knowledge of learning lexical bundles. The findings of the analysis have shown that students(pre-test) at the level of production score high and low rates concerning noun phrase based bundles. Whereas at the level of recognition students face difficulty in the recognition of clauses. Here, phrases are recognized more than clause are. The post-test which is concerned with those students who have attended lexical bundles classes shows high rates of correct answers in the use of noun phrase, verb phrase, preposition phrase and it cleft clause at the level of production and recognition. Therefore, learning such multi word expressions can contribute to gaining effective proficiency in language communication and competence