The existing frequency domain identification methods using fault records can not identify the transmission lines distributed parameters accurately, so this paper proposes a more accurate method of distributed parameter identification based on time-domain model. The method uses the fault voltages and currents measured at both terminals of the lines and calculates the line parameters by the least squares method in time-domain to avoid the error caused by vector transformation using frequency-domain method. It uses instantaneous symmetrical component method extracting sequence component to identify positive-sequence and zero-sequence parameters respectively in time-domain and uses LOWESS method smoothing fault signal noise to enhance the anti-interference performance of algorithm. The simulation results show that the proposed method can effectively identify the distribution parameters, and has high accuracy in a variety of fault conditions.