Provided is a welding method including: a sheet disposition process of disposing a first and a second protection sheet such that the first and the second protection sheet come into contact with a first and a second composite material and disposing an energization sheet such that the energization sheet comes into contact with the first and the second protection sheet; and a welding process of applying a voltage to a pair of electrode portions disposed at the energization sheet and welding the first and the second composite material, the energization sheet contains the carbon fiber base material oriented in a first predetermined direction connecting the pair of electrode portions, and the first and the second protection sheet contain the carbon fiber base material oriented in a second predetermined direction that substantially perpendicularly intersects the first predetermined direction.