The invention relates to a thermal machine fatigue testing method and a thermal machine fatigue testing machine adopting the same. The thermal machine fatigue testing machine comprises a machine frame, wherein a convex mould mounting base for mounting a simulating convex mould, a concave mould mounting base for mounting a simulating concave mould, and a driving device for driving the concave mould mounting base and the convex mould mounting base to perform relative motion so as to enable the simulating convex mould and the simulating concave mould to exert a pressure on blanks are arranged on the machine frame; the thermal machine fatigue testing machine further comprises a heating device for heating the blanks, a feeding device for continuously feeding the blanks to the heating device, a loading device for sending the heated blanks to a position between the simulating convex mould and the simulating concave mould , and a deloading device for deloading the pressurized blanks from the position between the simulating convex mould and the simulating concave mould. In the actual moulding process of the blanks, the blanks are heated first and then moved onto the moulds, and are moulded through mutual pressing action of the concave mould and the convex mould, so that actual service conditions of a thermal working mould are completely and effectively met, and a thermal machine fatigue result of the thermal working mould can be accurately tested.