T he present study is an attempt to investigate the effectiveness of cooperative language learning (CLL) in developing the main micro-speaking skills (accuracy, fluency and pronunciation) of a 28 randomly chosen sample of ESP first year university students of Faculty of Engineering, Alexandria, Egypt. In order to achieve the purposes of this study, two instruments were used: a) a student questionnaire for identifying ESP students' perceptions of CLL ,2) a teacher questionnaire for identifying ESP instructors' perceptions of their students' CLL, and c) an   oral test to evaluate the level of students' oral skills. A speaking teaching program (Rossita Stone Application, Basics+1-5) was used as an experimental intervetion. The sample was assigned to two groups (control and experimental); the latter was exposed to (CLL) whereas the formar to conventional teaching.. Findings of the study revealed that accuracy and fluency as speaking sub-skill,s improved remarkably both structurally and semantically which may be due to the learners' ability to recognize their ideas more adequately. Pronunciation, on the other hand, was the least developed sub-skill and this could be related to their unwillingness to run the risk of imitating the native accent.