This paper is concerned with disturbance rejection for data storage systems which applies microactuator to expand its servo bandwidth. An approach based on the generalized Kalman-Yakubovic-Popov (KYP) lemma together with the Youla parameterization is proposed which allows us to suppress disturbances of particular frequencies within or beyond the servo bandwidth via convex optimization. The rejection of narrowband high-frequency disturbances is achieved by using this approach. Simulation together with implementation results demonstrate the simplicity and effectiveness of the design method as compared with the traditional frequency weighting method. (c) 2007 Elsevier Ltd. All rights reserved.