This study addresses the issue of low energy utilization efficiency in graphite heating processes caused by system losses and non-directional radiation. To this end, a design method for graphite radiant heating devices that considers energy utilization efficiency has been proposed. First, the influence patterns of cable resistance and operational environment on graphite heating performance were analyzed, leading to the proposal of methods to enhance heating efficiency by adjusting graphite resistance and optimizing operational conditions. Second, a design approach for graphite heating devices capable of generating high radiation heat flux was established. Finally, based on the aforementioned methods, a high-heat-flux graphite heating device was designed and experimentally evaluated through platform testing of its heating capacity. The results demonstrate that the designed device achieved the generation of a 1.6 MW/m2-level radiation heat load, thereby validating the effectiveness of the proposed method.