In this study, the yaw misalignment value of wind turbine was measured using Lidar and it was analyzed the effect of vibration reduction and power performance improvement when applied to turbine. It was confirmed that the vibration of the main bearing and the gear box of the wind turbine was partially reduced. Also it was found that the output performance was improved when the wind speed was over 8m/s. As a result, it was also found that the annual energy production(AEP) was improved when the average annual wind speed of the wind farm was over 6m/s. Converted to AEP, the AEP improved about 1% and 4%, when the annual wind speed was 6m/s and 11m/s respectively, which resulted in an improvement of about 1~4% through the yaw misalignment correction of the wind turbine.