A sealing resin composition: contains a thermosetting resin component, a curing accelerator, an inorganic filler, an ion-trapping agent, and an aromatic monocarboxylic acid with an electron-withdrawing functional group obtained from a nitro group and/or a cyano group; is a solid at 25 DEG C; and has a sulfur content as measured by X-ray fluorometry of not more than 0.1 mass% calculated as SO3.