This paper deals with H-infinity model reduction problem for discrete-time Takagi-Sugeno (T-S) fuzzy systems with external disturbances assumed belong to finite frequency (FF) ranges. By applying the generalized Kalman-Yakubovich-Popov (gKYP) lemma, Projection lemma and introducing some key matrices to eliminate the product terms between the reduced-order parameters and the Lypunov matrices, an improved conditions is obtained for analyzing the H-infinity performance of the error system. Then sufficient condition in terms of linear matrix Inequalities (LMIs) are established for designing reduced-order model with a guaranteed H-infinity performance level. Finally, we demonstrate via numerical example that our method can achieve much smaller approximation error than existing results.