By now few researches deal with quantitative evaluation on risks of IT(information technology) outsourcing. In view of the characters of IT outsourcing, IT outsourcing can be divided into four stages as feasibility analysis stage, selections of IT outsourcing vendor, IT outsourcing vendor management and evaluation, terminate or continue outsourcing decision. According to every stage of outsourcing workflow,the paper builds the evaluation index system to calculate with the method of gray-fuzzy synthetic evaluation and deal with evaluation result quantitatively to build the risk evaluation system of IT outsourcing. Comparing the evaluation result with enterprise risk degree, can made outsourcing prewarning mechanism.
