In FY2 geostationary meteorological satellite, the ranging subsystem is an important part of the ground application system, whose success rate will affect the positioning accuracy of the satellite orbit and cause degradation of imagery resolution. This paper analyses all failures of ranging subsystem appeared in 2014, and Failure Tree Analysis was used to sort out the failures to get the failure factor weights, and then this method was verified through the failures appeared in 2015. Meanwhile, this paper also proposes corresponding solutions for each kind of failures to provide references to improve success rate of the FY2 ranging subsystem and gain valuable experience for future operation and maintenance of the future FY4 ranging subsystem.