The advanced operational software of the Lband upperair meteorological sounding software system is introduced, including the balloonreleasing program and the sounding data processing program. The system is programmed using the Borland C++ language under the Windows platform with an operational graphic interface according with the upperair operational criterion and is the backbone operational software system in the upperair meteorological sounding network of China Meteorological Administration (CMA). The longterm operational use of the software system shows that the software system is convenient to operate, has a userfriendly interface and strong functions, and has realized the automation from data sampling to data processing. The basic and exceptional processing functions of the software system and some typical troubleshooting examples are described. The future improvement of the software system, the design of the standard data interface, and the programming of the network software system are discussed.