A single-ended fault location method based on traveling wave natural frequencies for parallel lines on the same tower is proposed. The modal mixing phenomenon is judged by deriving the reflection coefficient matrix for different fault types. Then the appropriate modal is selected to estimate the traveling wave spectra and extract the dominant frequency. Finally， the location results can be derived from the relationship among fault distance， the natural frequencies and boundary conditions. Considering the influence of distributed capacitance on location results and the characteristic of the proposed algorithm， the frequency sensitive distributed parameter line model is used to establish the simulation system with PSCAD/EMTDC for simulation research. The simulation results under different fault conditions indicate that the proposed method has good accuracy and applicability.