The invention discloses a new energy generator set full power range harmonic characteristic model acquisition method and system. the method comprises the steps of acquiring a three-phase output voltage and a three-phase output current in a new energy generator set power generation test; performing fast Fourier transform on the three-phase output voltage and three-phase output current to acquire spectrum information of voltage and current data; acquiring each harmonic impedance under different working conditions according to the voltages and currents of the new energy generator set under the different operation conditions; and fitting each harmonic impedance acquired by multiple tests by using a polynomial least square method o acquire the final harmonic impedance characteristic model of the new energy generator set. The harmonic impedance characteristic model within the full power range acquired by using the method is universal, meanwhile performs analysis based on actually measured running data, and is higher in accuracy and reliability.