Abstract: Disclosed is an electroless metal film-plating system. While polyimide film is continuously fed from a roll, a series of wetting processes, including a degreasing process, an etching process, a neutralizing process, a coupling process, a catalyst-adding process, an undercoating process, and a plating process are conducted, in order, so as to plate one or both surfaces of the film with a conductive metal, followed by drying the conductive metal-plated film and taking up the plated film into a roll. A wetting process, in which the film passes through a liquid solution and is repetitively immersed in and drawn from a washing solution, is applied to all process parts, several parts notwithstanding, to produce a bilayer structure FCCL exhibiting superior physical properties such as peel strength. Also, after immersion in liquid in each process, the liquid is removed using wringing rollers so as to coat the material of interest at a uniform thickness.