Randomly Ag nanorod array has been demonstrated as highly sensitive surface-enhanced raman scattering(SERS)substrate due to its remarkable plasmonic properties in the visible range.In this work,Ag nanorod array has been prepared by the glancing angle deposition(GLAD)technique.A finite-difference time-domain(FDTD)method has been utilized to study the near-field electromagnetic field and the far-field spectrum when the array is illuminated by light.The scanning electron microscope(SEM)topography of the random Ag nanostructures is transformed to binary images to allow them to be simulated.