PURPOSE: To provide the titled composition for the insulation coating of electrical and electronic parts, composed of a novolac epoxy resin, a novolac phenolic resin and an inorganic filler, and having specific particle size and excellent moisture resistance, high-temperature electrical characteristics and heat-cycle resistance.

CONSTITUTION: The objective composition having an average particle diameter of 30W80μm is prepared by mixing (A) 40W80wt% of a novolac epoxy resin (having an epoxy equivalent of 180W250 and a melting point of 50W100°C), (B) 20W60wt% of a novolac phenolic resin (having a hydroxyl equivalent of 100W250 and a melting point of 50W120°C) and (C) an inorganic filler (containing silica powder as main component).