A miniaturized dualband bandstop frequency selective surface (BSFSS) is proposed and analyzed. The resonance frequencies of the proposed BSFSS can be adjusted by changing the structure parameters, and a miniaturized BSFSS centered at 3.84 GHz and 6.67 GHz is designed and simulated. The simulated results indicate that the designed BSFSS obtains bandwidths of 57.8% at 3.84 GHz and 12.9% at 6.67% GHz, and performs very well in the angle stability and the polarization stability within the operating bands. Besides, a whole size of the proposed BSFSS unit cell is only 7×7 mm2, compared with the conventional FSS unit, the integral size is reduced by 56.9% at least, and the advantages of miniaturization are obvious.