College students＇ administration is a systematic project, which is carried out in a complicated social environment and affected by many factors and facing many risks. But in the theory of our college administration system there are still not any risk indentification, analysis and evaluation systems and models. In this paper we adopt the grey evaluation theory to build the maths model and analyze some single risks in college students＇administration from the levels of risk effect and use examples to turn it out to be operationable.