There are provided copper particles and a copper paste for a copper powder-containing coating film which can be subjected to electroless metal plating without using an expensive catalyst such as palladium, and a process for producing a conductive coating film by subjecting a copper powder-containing coating film formed by using the copper paste to electroless metal plating or heat treatment with superheated steam. The present invention relates to a process for producing a conductive coating film comprising the step of forming a coating film on an insulating substrate using copper particles having an average particle diameter of 0.05 to 2 μm as measured by observation using SEM in which a BET specific surface area value (SSA) (m2/g) and a carbon content (C) (% by weight) of the copper particles satisfy a relationship represented the following formula [1]: C/SSA·7×10−2 [1], and a copper paste comprising the copper particles; drying the coating film to obtain a copper powder-containing coating film; and then subjecting the resulting coating film to electroless metal plating or heat treatment with superheated steam.