Provided is a curable resin composition capable of forming a cured product that has excellent heat resistance and transparency and, in particular, offers excellent barrier properties to a corrosive gas.The curable resin composition according to the present invention includes a polyorganosiloxane (A), an isocyanurate compound (B), and a silane coupling agent (C). The polyorganosiloxane (A) is an aryl-containing polyorganosiloxane. The polyorganosiloxane (A) preferably includes a polyorganosiloxane having a number-average molecular weight (Mn) of 500 to 4000 as determined by gel permeation chromatography and calibrated with a polystyrene standard.