The invention discloses a same-tower double-circuit transmission line fault location method. The method includes collecting the voltage and current fault components on both sides of the same-tower double-circuit transmission line, and extracting the voltage and current fundamental components; decoupling the voltage and current fundamental components on both sides of the same-tower double-circuit transmission line into independent six-sequence components by means of a six-sequence component method, namely, a same positive sequence T1, a same negative sequence T2, a same zero sequence T0 and an inverse positive sequence F1, an inverse negative sequence F2 and an inverse zero sequence F0; determining whether there is an inverse negative sequence current component in the six-sequence current components, if yes, using the fault location method based on the inverse negative sequence current component; if not, using the fault location method based on the same positive sequence current component. The fault location method provided is high in positioning precision and low in measurement cost.