In order to improve the efficiency and reliability of the graphite heating element, this paper investigates the failure process of graphite heating device, and determines the reliability quantitative index of heating element, temperature uniformity; four circuit parameters to quantify the output performance was advanced, the thickness, the width of the strip, the gap between the strips, and the radius of the gap rounding. The mechanism of influence of cir-cuit parameters on heating capability and reliability was investigated through coupled thermal electric finite element method analysis. The results show that the thickness determine the heat output capability, while the remaining three circuit parameters determine the reliability. The advancements in this paper play an important role in the development of high performance graphite heating device.