The invention provides an ordered porous array built by a sliver and tantalum composite material as well as a preparation method thereof. The preparation method comprises the following steps: depositing a sliver and tantalum composite film through magnetron sputtering, putting a completely cleaned monocrystalline silicon slice under vacuum and depositing a chromium film; controlling the current intensity, accurately regulating and controlling the deposition rate of silver and tantalum elements separately, maintaining the reaction pressure of a chamber, performing continuous sputtering deposition, plugging gap formed in the deposition process of the silver by the tantalum element, and forming the ordered porous array built by the sliver and tantalum composite material under proper deposition rate of the silver and tantalum elements. Along with the increment of the tantalum deposition rate, the film surface porous array can be heavily plugged by the tantalum element, and smoother film surface appearance is further formed. The sliver and tantalum composite material ordered porous array prepared by the method is simple in preparation process, large in specific surface area, convenientin large-area growth, low in cost, avoids organic compound pollution on the surface of the film, and can be widely applied in the fields of SERS sensing, metal catalysis, nanometer probes, photoelectric devices, solar batteries, adsorbing materials and the like.