Provided is an electrical insulation resin composition that exhibits a high cracking resistance, a high thermal conductivity, and a low viscosity during molding. This electrical insulation resin composition contains an ester bond-containing resin 1 and a silica filler, and the silica filler contains a pulverized crystalline silica 2 and a fused silica 3 and has the following numerical limitations. 1) The silica filler is at least 65 mass% and less than 75 mass% of the overall resin composition, and the proportion of the fused silica 3 in the silica filler is 45 to 50 mass%. 2) The silica filler is at least 75 mass% and less than 80 mass% of the overall resin composition, and the proportion of the fused silica 3 in the silica filler is 35 to 40 mass%. 3) The silica filler is at least 80 mass% of the overall resin composition, and the proportion of the fused silica 3 in the silica filler is 30 to 40 mass%.
