In present work,a new kind of electrolytic deposition method to make carbon atoms activated to obtain carbon film in molten salt was developed.An attempt of synthesizing carbon film on nickel substrate was first performed.It is found that carbonate ion concentration is one of the most important factors to obtain the carbon film.Pulse introducing in the electrolytic method and decreasing carbonate ion concentration reasonably are useful to get the carbon atoms activated,to accelerate the growth of deposition coating and to improve its quality.The experimental results on various(substrates) indicated that carbon film can be synthesized on the substrate of nickel,copper,iron and titanium by electrolytic deposition method in molten salt under suitable experimental conditions.