The invention relates to a PMU measurement-based method for identifying complete parameters of double circuit lines on the same tower of a short line, the PMU measurement-based method comprises the following steps of 1, according to whether a short-circuit same-pole parallel double-circuit line is symmetrical or not, respectively establishing impedance models of short-circuit same-pole parallel double-circuit lines with an in-phase sequence and an out-of-phase sequence; 2, establishing a parameter identification target function of multi-moment PMU measurement based on a least square method; 3,respectively selecting PMU measurements at N moments and N+1 moments, and substituting the PMU measurements into the parameter identification target function established in the step 2 to obtain corresponding parameter identification results alpha N and alpha<N+1>; for the in-phase sequence line, setting an initial value N to be equal to 2; for a non-in-phase sequence line, setting an initial value N to be equal to 4; 4, judging whether alpha N and alpha<N+1> in the step 3 meet the condition that |alpha N-alpha<N+1>| is smaller than or equal to lambda or not, if yes, quitting the cycle, and completing parameter identification; if not, enabling N to be equal to N+1, and executing the step 2 again for recalculation until parameter identification is completed. According to the method, the impedance parameters of the short-circuit same-pole parallel double-circuit line can be accurately and quickly obtained.