An epoxy resin composition of the present invention includes an epoxy resin, a curing agent, an inorganic filler, and a curing accelerator, in which a maximum exothermic peak temperature in a DSC curve of the epoxy resin composition obtained in a case of elevating a temperature from 30°C to 200°C under a condition of a temperature elevating rate of 10°C/min using a differential scanning calorimeter is equal to or higher than 80°C and equal to or lower than 145°C.