The paper proposes an efficient and wideband polarization rotator composed of two-layer surfaces for millimeter wave applications. The simulations show that polarization conversion ratio (PCR) is completely efficient and higher than 95% for both polarizations (x and y) normally incident EM waves so that the bandwidth is ranged from 19 GHz to 49 GHz, equivalent to 88% relative bandwidth. The mechanism for linearly polarization rotation is described by decomposed electric field components that couple with different resonance modes of the structure. Besides, the surfaces are approximately robust under the incident oblique angles. The suggested structure with the excellent efficiency of polarization conversion has various potential applications in different areas such as imaging, modern communications, and new polarization-control devices.