Filters are essential components in the signal transmission process, serving to screen and filter transmitted signals. In this paper, we propose a novel resonator structure designed for narrow-band filters. The electromechanical coupling coefficient is reduced by stacking heterogeneous piezoelectric films with oppositely oriented c-axes. First, the fundamental principle of the new narrow-band resonator structure is explained through finite element simulations. Furthermore, the traditional Mason circuit model is modified to account for the structure of the proposed resonator. Two transformers associated with four-port transmission lines are employed for the electrical modeling. A comparison of circuit simulation and finite element simulation results is presented to verify the accuracy of the equivalent circuit model. Finally, a basic narrow-band filter is constructed using the widely recognized ladder-type topology. The transmission characteristics of the filter are obtained through simulation, confirming the reliability of the narrow-band filter design.