Abstract: This paper considers the designs of static state feedback controller and dynamical reduced-order output feedback controller for a class of systems simultaneously with matrix parameter uncertainty and independent uncertainty structure which is described in the form of integral quadratic constraint. Then three problems are considered: the robust H∞ stability problem for systems only with IQC uncertainty structure based on dissipative dynamical system theory, the robust H∞ disturbance attenuation problem with static state feedback controller, and the robust H∞ disturbance attenuation problem with dynamical reduced-order output feedback for systems simultaneously with parameter uncertainty and IQC uncertainty structure. All the solvable sufficient conditions can be transformed into the form of LMI.