The two causes ofCorrection of lidar measured turbulence the errorValidation inTurbulence turbulence measurementTurbulence measurement by using vertical profiling lidar, namely the error due to the spatial separationSpatial separation induced measurement error of the data points in conical scan and along the line-of-sightConical scan and line-of-sight (LoS), are investigated by using synthetic turbulent windTurbulent wind field. Firstly, the main source of the error from the spatial separation in the conical section is generated by the vertical component of the turbulenceTurbulence. It is found that large vertical turbulenceTurbulence causes overestimation and small vertical turbulenceTurbulence causes underestimation of the horizontal turbulenceTurbulence. Due to the separation of the measurement point along the LoS, the lidar measured turbulenceTurbulence is underestimated. A correction method is then proposed considering these two effects. Finally, the proposed correction method is applied to the lidar measurementLidar measurements at Choshi Met Mast. The vertical profiling lidar measured 90% of the turbulenceTurbulence intensity after applying the proposed method shows good agreement with that measured by the sonic anemometer. It is noticed that when short-term of the measurement is used for validationValidation, the errors cancel out each other and the wrong conclusion may be obtained.