There is provided a method for electrically energizing and heating a platinum or platinum-alloy composite tube structure having a structure including a first main tube, a second main tube, and a branch tube connecting the first main tube and the second main tube, which prevents a local part of the branch tube from being electrically energized and heated in an excessive or insufficient manner. There is provided a method for electrically energizing and heating a platinum or platinum-alloy composite tube structure having a structure including a first main tube, a second main tube, and a branch tube connecting the first main tube and the second main tube, the method comprising dividing an energizing path for the branch tube into a first energizing path from the first main tube to the branch tube and a second energizing path from the branch tube to the second main tube; and performing energization control for the first energizing path and energization control for the second energizing path independently of each other.