For the defects of existing lightning location methods for transmission lines, a new combined lightning locating algorithm is proposed. It takes into account the characteristics and application of Lighting Location System (LLS) and one terminal location methods. Firstly, existing LLS is adopted to recognize the lightning distance approximately. Then, the accurate arriving times of wave fronts are obtained with this approximate distance and the line parameters, which involve the reflected wave fronts from the fault point and the opposite terminal of fault line. Finally, accurate results are obtained with one terminal location methods. The algorithm overcomes not only the effects of the geographical environment, detection stations distance and other factors on the locating accuracy of LLS, but also the shortage that the locating accuracy of the single-ended traveling wave method can not be guaranteed because of the difficulty in recognizing traveling-wave fronts. Under lightning stroke fault, locating formula makes full use of measured data, which eliminates the effects of velocity’s uncertainty and the error brought by the conductor sag and the change of line length on the measurement data to a certain extent. The EMTP simulation results verify that the algorithm is correct, and lightning locating accuracy is greatly improved.