An epoxy resin composition includes: (A) epoxy resin; (B) a curing agent; (C) 0.1 to 10 mass % of silica filler with an average particle size of 10 nm or more and 100 nm or less; and (D) 40 to 75 mass % of silica filler with an average particle size of 0.3 μm or more and 5 μm or less. The component (C) and the component (D) are contained by 40.1 to 77 mass % in total.