Cooperative learning is a kind of teaching theory and strategy system based on group. The theory of cooperative learning has been applied in college English teaching and has proved to be fruitful and beneficial. Cooperative learning as a breakthrough and complement against traditional classroom instruction is an efficient teaching approach, which can promote learners' cognitive ability and improve their competence to use language. This paper intends to discuss the significance of cooperative learning and how to apply this approach in college English teaching to improve students' overall language competence. Problems faced with the application of cooperative learning are also analyzed and proper solutions are suggested to tackle the problems.