In this paper, a touch fault calculation method is proposed based on symmetric coordinate method. The touch fault in this paper means that a line-to-line short circuit fault occurred on parallel transmission lines stringing on a same tower. It is known that the touch fault occurs very rarely such as the galloping phenomena, and it causes an abnormal voltage rise especially on a low-voltage transmission line. However, a quantitative analysis method of the abnormal voltage has not been proposed. Therefore, a general analysis method of the voltage profile solution for the touch fault is proposed based on symmetrical coordinate method. The proposed method is able to calculate the precise voltage and current profile solution efficiently by introducing the similar formation for the touch fault solution same as the general fault solution. Demonstrative result to the application in the touch fault calculation is presented in order to verify the practicability of the proposed method.