This paper introduces a new technique for synthesizing three-dimensional (3D) frequency selective structure (FSS) with second-order Chebyshev bandpass filtering response. The proposed unit cell of the FSS is composed of two resonators cascaded through a slotline structure. Physical mechanism of the proposed FSS is explained with the aid of an equivalent circuit model. Detailed synthesis procedure of the FSS is then presented based on the second-order Chebyshev bandpass filter. Meanwhile, an example with a fractional bandwidth of 10% at 10GHz is designed, fabricated and measured. The measured results demonstrate that stable bandpass filtering response is realized by the simple structure under a large variation of the electromagnetic incident angle.