The present study aims to investigate the significance of using cooperative group work on improving students’ speaking production and communicative skills in EFL classes. The present work is mainly attempts to investigate the students’ awareness of the important of speaking skills in learning English at some high schools in Thai Nguyen province, Vietnam. The results of the study show that most of the students think that speaking is difficult for them because of the lack of real practice. They all agreed that cooperative group working will help them to talk more in a speaking class. It is also true for teachers who participate in the semi-structured interview. The findings from this research provide evidence that cooperative group work is the right technique for developing students’ language use and increasing their classroom oral participation in interactional environment.