The invention discloses a differential composite chemical plating method. The method is namely a ''horizontal-type'' composite plating method which comprises the following steps: firstly, partitioning a to-be-treated surface of a work piece and then respectively plating each independent sub-region to gradually finish overall plating from point to surface. The method disclosed by the invention is used for realizing transformation of surface treatment from conventional homogenization to novel differentiation, so that the surface treatment is higher in pertinence and lower in cost. By utilizing the technology provided by the invention, each prepared independent plated layer can also be regulated to have difference in electrochemical positive polarity and electrochemical negative polarity, so that the protecting and protected relationship of the plated layer/base body and the plated layer/plated layer can be built by utilizing an electrochemical theory of a sacrificial anode/cathode protection method and the aim of implementing key protection on key surfaces of the work piece is finally realized to prolong the service life of the work piece and widen the application field of the work piece.