A manufacturing method for a carbon heat source comprises: a step A1 of forming a first groove in a state where the plurality of carbon members are aligned in one line; a step A2 of changing, subsequent to the step A1 being performed, an orientation of the plurality of carbon members so that the first groove formed in the plurality of carbon members crosses relative to the first predetermined direction in a state where the plurality of carbon members are aligned in one line; and a step A3 of forming, subsequent to the step A2 being performed, a second groove in a state where the plurality of carbon members are aligned in one line.