The process of cooperative learning involves students working together in small groups on a structured activity. This type of learning differs from the traditional, teacher-centered classroom in that it is student-centered. In a traditional classroom, the teacher plays the role of “learning disseminator”, giving the students all of the information they need. In a cooperative classroom the teacher takes on the role of “learning facilitator”, helping students figure out what information will be helpful to complete the assigned task. The purpose of the present article is to reveal the effect of cooperative learning on language skills in an English course. It is highlighted the fact that cooperative learning has a larger effect on vocabulary knowledge, grammar, listening and reading skills compared to traditional methods.