The invention provides a bandpass filter, comprising: a substrate with a plurality of dielectric layers; a plurality of resonators; and a plurality of ground layers each having one slot arranged on; wherein the plurality of resonators are arrayed vertically each on respective one of the plurality of dielectric layers alternately without any of offsets, and each of the plurality of ground layers is between adjacent dielectric layers. Adjacent slots are arranged in opposite sides of the ground layers. The invention also provides a method of fabricating the bandpass filter.