The liquid thermosetting resin composition of the present invention comprises an epoxy resin in which at least one selected from the group consisting of a linear epoxy resin having a degree of polymerization of 2 or more and an epoxy acrylate resin and at least one selected from the group consisting of a novolac-type epoxy resin and a naphthalene-type epoxy compound are linked to each other via an ether linkage, and which has a weight average molecular weight of from 2,000 to 10,000. When the liquid thermosetting resin composition of the present invention is used for insulating a stator coil of a rotating electric machine, mechanical characteristics can be improved without causing a reduction in the heat resistance.