As China enters WTO, more college graduates with higher oral English proficiency are required. However, we learned that even students in some distinguished universities are lack of this ability. Based on her teaching experiences and the theory proposed by Krashen and some other well-know foreign languages teaching researchers, the author of this thesis formulated two hypotheses: 1) Students' listening ability and their oral English production ability are correlated. 2) Teachers who bring listening and audio-visual materials into oral English class are likely to have better teaching results. Krashen's Comprehensive Input Hypothesis is the theoretical foundation of the author's research. The author studies the nature of listening and speaking, by doing so she points out the effects of listening on improving students' oral English from two broad aspects. This thesis aims at making a quantitative analysis on the effects of listening on speaking for college students. With the help of SPSS 11.5 software, a quantitative computerized analysis on this research hypothesis is made. Moreover, a quantitative analysis on correlation between listening and speaking is also made. The result shows that listening and speaking ability are closely related, and listening does have positive effects on improving college students' oral English.