Harmonic is one of main concern in Wind Power Plant (WPP) as growing usage of power electronic converter is observed. Besides the injection of harmonic by individual wind turbine (WT) as source of harmonic, its propagation in network and problem of resonance is also an issue. By implementing passive filter for harmonic mitigation, additional resonance peak is observed due to its interaction with system side impedance. This paper explores the solution for harmonic mitigation with capability of damping resonance in WPP. An aggregated model of 400-MW WPP network is analyzed in correlating resonance and amplification. A passive filter and hybrid filter is designed to mitigate harmonic accordingly. It is shown that hybrid filter able to provide damping capability and improve the performance.