The objective of this paper is to highlight the importance of Computer Assisted Language Learning when it comes to helping the multilingual learners improve their English pronunciation. We look at the multilingual learners of first year engineering college students in Hyderabad. The study is limited to the students of first year B.tech. The learners are from different countries like South Sudan, Afghanistan, Nepal and also from different states like Bihar, Bengal, Maharashtra, Telangana and Andhra Pradesh. The classroom consists of varied factors, multicultural and multilingual background, apart from their first language influence. Besides, we examine the quantity and quality of L2 phonetic input account for much of the variation in the degree of foreign accent found across adult L2 learners. This paper first provides an overview of factors that constrain ultimate attainment in adult second language (L2) pronunciation. For the current study we look at two Nepalese speakers, eight Afghan speakers, two each from Bihar, Sudan, Bengal, Maharashtra, Telangana and Andhra Pradesh. These speakers were trained to recognize and produce English vowel sounds. Using a specially designed computer application, learners were randomly presented with recordings of the target vowels in monosyllabic frames, produced by native speakers. Pre- and Post-tests of the learners’ English vowel pronunciation indicated that their vowel intelligibility significantly improved as a result of training, not only in the training context, but also in an untrained context. Key-words: Computer Assisted Language Learning, Multilingual learners, L2 Training