A protective film 10 of the present invention includes a base material layer and a pressure sensitive adhesive layer, and is used by being attached to a resin substrate 21 at the time of performing heat bending on the resin substrate 21. The pressure sensitive adhesive layer contains a polyolefin having a melting point of lower than 125° C. The base material layer has a first layer which contains a polyolefin having a melting point of 150° C. or higher, and a second layer which contains an adhesive resin. In a case of heating the protective film 100 having such a configuration, in a state of being interposed between two attaching substrates which are formed of polycarbonate, at 145° C. for 30 minutes, peeling off one attaching substrate on the side of the pressure sensitive adhesive layer at 25° C., and then viewing a surface of the one attaching substrate in a plan view, a residual ratio of an area where the pressure sensitive adhesive layer remains is 5% or less.