To compare the consistency of cloud base heights measured by some instruments, the Meteorological Observation Center of China Meteorological Administration firstly organized a nearly 5-month campaign employing four ceilometers, two infrared cloud measuring systems, one Total-Sky-Imager and one cloud radar. The campaign was carried at the observation field within the campus of Nanjing University of Information Sciences & Technology. Preliminary analysis of 3-month cloud base heights obtained from most of the above instruments shows that the data among 3 ceilometers are comparatively consistent, the consistency between the two infrared cloud measuring systems is slightly worse than that from ceilometers, the consistency of observed cloud base height of the first cloud layer between cloud radar and ceilometers is comparatively low, but is much better than that between cloud radar and infrared cloud measuring system.