A heat treatment method according to the present invention includes a preliminary-state-generating step of heat-treating an alloy that undergoes multiple-step transformation with temperature by bringing the alloy in contact with a contact-type heating element for 0.01 sec or more and 3.0 sec or less, the contact-type heating element being adjusted to a particular temperature within a preliminary-state-generating temperature region determined on the basis of a first temperature related to a particular first transformation of the alloy and a second temperature, which is higher than the first temperature, related to a particular second transformation of the alloy so as to generate a preliminary state in the alloy.