Atmospheric observing system operations and monitoring (ASOM) is a realtime monitoring system of observation equipment’s running status and observation data. In this article, four operating indexes including availability of operation (Ao), mean time between failures (MTBF), failure duration (Tfd), number of failures (Nf) are evaluated on the basis of maintenance data of ASOM from 1 December 2009 to 30 November 2014. For the 2014 indexes, Ao and MTBF increase to 99.06% and 1465.08 h respectively while Tfd and Nf reduce to 13.15 h and 4.68 times. In addition, the failure distribution and replacement of radar spare parts in these fault cases and their trends are quantified and evaluated for different radar subsystems and different types of radar. The results, to some extent, make efforts to set up pertinent spare parts supply management, improve maintenance support capability of CINRAD, and, eventually, promote efficiency of China’s meteorological observation equipment management.