Classroom silence has always been the issue that exists in oral English classroom and that needs to be addressed.It will not only hamper the effective interaction and communication between teacher and students,but is the result of students’spoken practice.This study focused on the two agents in classroom interaction:namely,the teacher and the students,to find out the causes and further explore the implications for college English teaching.This study found out many aspects leading to classroom silence which are students’learning motivation,language proficiency,students’personality,teaching material,and teaching method.Thus,measures from the perspective of Interaction Theory were proposed.In the long run,students will increase their classroom interaction in a certain degree until the present teaching problems are solved.