Graphene oxide and reduced graphene oxide films have widespread applications in many fields. There are several methods for preparing thin films of these materials in different substrates, but a method that offers low cost and high quality in thin-film fabrication is still lacking. Here, we report a low cost and easily scalable methodology to produce reduced graphene oxide conductive films in polyethylene terephthalate (PET) substrates from graphene oxide suspensions. In an environmentally friendly approach, the reduction process was carried out in a green chemistry fashion way using ascorbic acid as reduction agent. Graphene oxide was synthesized by modified Hummers' method and the coating was realized in a homemade dip-coating process. Films with light transmittance as high as 99% and surface resistance in the order of MΩ/sq were obtained with graphene oxide contents as low as 0.5 wt%. The increase in graphene oxide contents produced films with surface resistance as low as 13 kΩ/sq. These are very interesting results that allows these films to be considered for application in electromagnetic shielding and electrostatic dissipation.