Cryogenic preservation of semen is a useful technology for maximizing fertility and genetic diversity when breeding endangered species in captivity. In order to explore the technology of semen cryopreservation and the way to use it for artificial insemination of rare crane in captivity, a semen cryopreservation research on Siberian Crane (Grus leucogeranus) was undertaken at Beijing Zoo from 2003 to 2005. The semen of Siberian Crane was collected then preserved by freezing, the frozen semen was used subsequently for insemination. From fifteen times of semen collections, thirty-six 0.2 ml samples were frozen. Frozen semen was thawed for AI sixteen times, The Beltsville Poultry Semen Extender was used, adjust pH to 7.8, and the osmotic pressure to 300 mosm/L (773 kPa) with distilled water, with 12% dimethylsulfoxide (DMSO) as the freezing solution to protection the sperms during cryopreservation. Semen is diluted with (3.2±1.1) times the volume of crane extender when it was collected. DMSO was added in the lab, the quantity of 12%DMSO was half volume of the diluted ejaculate, DMSO and diluted ejaculate were be at the same temperature (0-4℃) when they mixed. The ejaculate was equilibrated with DMSO for 15 min at 0-4℃ in the freezer. The samples were put into 0.2 ml each in freezing tubes for cryopreservation. Frozen semen was kept in the liquid nitrogen following three temperature-fall steps: 4℃--20℃,-20℃--80℃,-80℃--196℃. Frozen semen was thawed into 0-4℃ water for 3-5 min, and the semen was inseminated immediately after thawing. The rate of living sperms after thawing was (29.3±15.5)%(n=16). Insemination of the Siberian crane with frozen semen was undertaken each day during egg laying period, and insemination within four hours after each laying egg as soon as possible, using the equivalent of two to four ejaculates for each insemination to make up the loss of sperms during freezing. Experament of Artificial insemination by frozen semen was undertook for two eggs of each cluth in 2004 and 2005, One egg was fertile from five eggs laid in two years, with one chick was bred successfully from frozen semen.