A survey and comparative analysis of the family backgrounds of the entire undergraduate student body of X University and the group of student union cadres shows: the proportion of college students who serve as student union cadres who come from cities and have families with high social status, high family income, and parents with high educational backgrounds is greater than that of college students from the rural areas with families with low social status, low family income, and parents with low educational backgrounds. The reason is: there is uniformity in the cultural habits of college students who come from middle and high strata and the student qualities required by the student union; the self-alienation and rejection from the student union of college students from the low social class aggravates the trend of the low probability that they will become student union cadres. [This article was translated by Jeff Keller.]