A method for preparing a porous conductive coating on a plastic surface relates to a method for plastic surface treatment, in particular to a preparation method for obtaining a layer of porous conductive coating on a plastic surface. The porous conductive coating can provide a good substrate for the conventional electroplating (galvanic plating) and ion plating and a method for preparing a porousconductive coating on a plastic surface. Resin is added in an organic solvent, is added with a dispersant and non solvent materials after dissolution, and is added with nano-conductive material particles and leveling agents to mix evenly and then nanometer modified polymer latex is prepared; the plastic surface is activated by sulphuric acid and acetic acid or sodium hydroxide after being cleanedand de-oiled, and is dried to reserve; the nanometer modified polymer latex is sprayed on the dried plastic surface to be dried and activated by the mixed acid of sulphuric acid, hydrochloric acid and acetic acid, namely, a layer of porous conductive coating is prepared on the plastic surface.