Abstract: Nanometer Ag film is deposited on the interface of surface active agent and electrolyte by electrodeposition process. By comparing the electrodeposition rate and the particlesize of nanometer Ag film prepared by methyl sulfonic acid silver system with those of nanometer Ag film prepared by nitrate silver system under the same conditions, it is found that the particlesize of nanometer Ag film electrodeposited with nitrate silver is smaller and the growth rate of the nitrate silver nanometer film is faster. During the experiment, the silver grain was smaller and the distribution was more uniform in the nitrate silver electrolyte than in the methylsulfic silver electrolyte. That’s the reason why the nitrate silver system is selected as the electrodeposition system. For the nitrate silver electrolyte, the depositing current increases with the increase of concentration and voltage. The effect of cell voltage, concentration and temperature of electrolyte and pH value of the solution on nanometer film preparation has been analyzed. The optimal conditions on which the needed nanometer film was prepared: the concentration of the nitrate silver is 5 mmol/L, the voltage is 4 V, the pH value is 3.0 and the concentration of stearic acid is 0.2 g/L. The experiment indicates that grain diameter of Ag nanometer film deposited under the optimum conditions is about 20 nm on average and the grain shape is roughly spherical. The Ag nanometer film prepared with this method can be used in nonlinear optical material.