Summary: It is a problem that users’ reputation distributed in each domain can’t be shared in collaborative environment of cross-domain. A computation model of comprehensive reputation based on fuzzy regression is proposed in this paper to supply uniform reputation evaluation method which is the base of collaboration of cross-domain users. The model builds up user’s reputation vector of single domain, and the vectors are combined according to weighting coefficients. In order to build up fuzzy regression model, the comprehensive reputation is hazed with symmetric triangular fuzzy number to determine fuzzy coefficients, and to calculate out the result. The experiment results show that the model reflects the flexible range objectively.