OPGW is the abbreviation for the optical fiber composite overhead ground wire. The distribution of the current on OPGW has a significant influence on the power system，designing and selecting the OPGWs. We apply the improved phase component method to analyze the quantified calculation of the current flowing on the OPGW lines with the asymmetric short-circuit. Traditional phase component method usually regards the phase wires as analysis system. The improved phase component method is on basis of the traditional phase component method and takes the OPGWs into consideration, resulting in forming the phase wires and OPGWs as a complete system. To prove the correctness of the theory and calculation results，this paper compares the results with those from EMTP simulation software. This theory provides a method to calculate the fault currents along the transmission line. At last, the conclusion is been verified in an actual project example.