Abstract: In order to obtain a high transmission efficiency waveguide structure, a metal-dielectric-metal waveguide (MDM) grating structure is designed in this paper. The transmission performance of the grating structure is simulated by using finite-difference time-domain (FDTD) algorithm. The transmission of the visible to infrared spectrum through the waveguide grating is investigated by optimizing the structure, materials and other parameters of the waveguide grating.The results show that the waveguide structure has good transmission performance in the visible light range. The optical transmittance to 450 nm is 82.8% in the gold waveguide and 75% to the wavelength 400-450 nm in the silver waveguide. When the grating period is 450nm, the transmittance of the structure reaches 86% after the optimization of the structure in the visible range.