The next one to two years, the college student volunteers serving western China are experiencing a new period that transmit from post-80s to post-90s, so studying the willingness and influencing factors of post-90s college students volunteering to the west become more and more important. Based on the survey data, we will conduct descriptive analysis of the general situation of the post-90s college students to the west and use the Ordered Probit regression model to describe its influencing factors. Regression results find that household register and the level of college students understanding the policy affect their willingness to serve west. At last, on the basis of summarizing the research conclusion, several thinking and suggestions will be given from three aspects: individual, school and country.