Weather conditions for airplane icing and icing characteristics are analyzed on the basis of the measurements from 90 airplane flights from March 2000 to June 2005. The PSU/NCAR MM5 model is used to replicate the process of precipitation enhancement on 16 May 2005 in Shandong, and the simulation results show that the evolvement and range of the event agree well with observation. On the b asis of success simulation, a contrast experiment between the icing index from the model output and airplane measurements is conducted. The results show that reverse troughs and cold fronts on the ground are the main weather systems during the airplane precipitation enhancement season in Shandong; the greatest percentage of mild and moderate icing occurs along with surface lowpressure troughs, but the highest probability of icing is along with Southern Cyclone, up to 53.3%. The superposed field of the icingindex from MM5 model output and vertical velocity fields can be used to describe well the area, time and intensity of icing in precipitation enhancement operations.