This paper considers the problem of H∞ output feedback control with spectrum constraints for a class of uncertain stochastic systems. The purpose is the design of dynamic output feedback controllers such that the closed-loop system is asymptotically mean-square stable with a specified stability degree and an H∞-norm bound. First, the concept of spectrum for stochastic systems is redefined, and some characterizations about the stability degree are presented. Then, several equivalent conditions for the existence of H∞ dynamic output feedback controllers are obtained, and the explicit expression of a desired controller is provided. Furthermore, by using the cone complementarity linearization iterative algorithm, a detailed design algorithm is proposed. Finally, an example is given to show the effectiveness of the proposed method.