With high repetition rate of laser measurements, the airborne lidar system is capable to provide massive number of points with three dimensional coordinates. These measurements can be used for DEM production. The height accuracy of airborne lidar measurements reaches decimeter level. But the horizontal accuracy of the lidar points is difficult to evaluate due to the uncertainty of the scattered points. This study measured the horizontal coordinates of signalized points in the lidar intensity image. These signalized points were formerly established for the geo-referencing of satellite images. It is found that the horizontal accuracy of lidar points are in the range of -0.483∼+0.785 meters, roughly 1/2000 of the flying height of the mission. The number of laser points on the target of signalized point is found not related to the horizontal accuracy.