The test procedure and result analysis of the comparative observation experiment on some laser ceilometers at Beijing Meteorological Observatory and Changsha Meteorological Service from June to October 2014 are introduced. Fifteen instruments from four manufacturers were tested in the experiment that lasted for more than three months. The experiment used the observation results of HYCL51 and CYY2B Laser Ceilometers as the standard cloud heights. The artificial observations played a subsidiary role in testing the accuracy of these instruments when cloud heights are detected. The results show that observation omission and misjudgment tend to happen to all these laser ceilometers. Fog and haze impact the performance of the instruments significantly. Comparatively, HYCL31 has a higher accuracy rate, which can meet the needs of meteorological service.