The invention discloses a preparation method of a surface silver-plated conductive filler, which comprises the following steps: 1) ultrasonically dispersing a substrate in an ethanol solution and deionized water respectively, adding a polyphenol solution and a transition state metal ion salt solution successively to obtain a substrate with polyphenol-metal ion complex depositing on the surface; 2)dropwise adding ammonia water into that silver nitrate solution until the precipitate disappears, and preparing the silver plating solution; 3) placing the substrate prepared in the step 1) in the silver plating solution prepared in the step 2), adding a dispersant polyvinylpyrrolidone for stirring, 4) adding a reducing agent solution to the solution in the step 3) under stirring conditions, andreacting at room temperature for 20 to 120 minutes to obtain a substrate with a silver layer on the surface. The preparation method of the invention is simple and convenient to operate, greatly shortens the modification time, saves cost and time, and has good adhesive stability performance and conductive performance of the obtained conductive filler.