An analysis is made of the data from a comparative observation test for cloud height Indicators, which was carried out at the Beijing Meteorological Observatory from December 2011 to June 2012 The Sigma Space Micro Pulse Lidar (MPL) was used as a reference along with visual assessment. The observational data of different weather conditions are analyzed mainly from the aspects of false layers, missed layers, and layer height comparability, respectively, as well as high and low visibility. There is also an assessment towards the detection capability for several typical cloud genera. The results indicate that ceilometers are in good consistency with MPL; aerosol particles (fog, haze) in the atmosphere are the main cause of inaccurate measurements; the capability of ceilometers can be improved by increasing the single laser pulse energy and optimizing the optical system.