Proposed in this paper is a compact dual-band filter based on the combined resonators,in which the two central passband frequencies and bandwidths are all tunable.The filter is composed of two sets of l/4 microstrip resonators that produce two different passbands.By adjusting the coupled spacing between the adjacent resonators in each set,the bandwidth for either the lower or the upper passband can be independently adjusted.Moreover,a dual-band filter operating at 2.4 and 5.2GHz is designed and manufactured.The measurement results basically accord with the simulation ones,which validates the effectiveness of the proposed design.