Objective This paper investigated the traveling wave fault location in n-section ground-overhead mixed transmission lines and proposed a traveling wave fault location method based on time linear fitting. Methods Firstly the fault area was determined to identify the region where the fault occurred. Next different wave impedance lines were normalized to reduce ranging errors caused by different wave speeds. Finally the time linear fitting method was used to accurately locate the fault. Results This method addressed the difficulty in identifying the initial traveling wave head and reduced ranging errors caused by changes in traveling wave speed with transmission distance. Conclusion A simulation model of a 500 kV ground-overhead mixed transmission line was built in MATLAB / Simulink. The experimental validation results demonstrate that this fault location method can effectively overcome the inapplicability of the dual-end traveling wave ranging method due to different wave speeds and ultimately achieve precise fault location.