The invention discloses a silver nm particle array template, which is prepared by a self assembling method. The average size of the silver nmo particles is 10 to 500 nm, and the density is 10 <8> to 10 <12> / cm <2>. The invention also discloses a preparation method of the silver nm particle array template, and the process steps are as follows: step one, a layer of uniform silver film is deposited on a base plate by using vacuum deposition film equipment; step two, discrete nm particles are formed to the deposit silver film through heat annealing process, therefore, the silver nm particle array template distributed at random can be prepared. The invention has the advantages that the silver template is prepared with the self assembling method, the average size of the silver nm particles is 10 to 500 nm, the density is 10 <8> to 10 <12> / cm <2>, and the size and the density of the nm particles can be controlled by the thickness of the silver film; the preparation method is simple, the operation is easy, and the cost is low; the silver template has the advantages of high density and random distribution, thereby being helpful to the design and the production of the device products of magnetic recording media, and flat field emitters and so on.