From September 2003 to September 2005 a population of five groups of black crested gibbon (Nomascus concolor jingdongensis) was monitored for 15 to 20 days each month in Dazhaizi, Wuliangshan National Nature Reserve, central Yunnan, China. Data on population size, mating system, birth intervals, death rate, carrying capacity and catastrophe were collected and used with the computer program Vortex 9.14 to simulate population dynamics of the black crested gibbon in Dazhaizi. Results of the simulation suggest that in the absence of poaching the population will reach carrying capacity within the next 100 years. However, a modest harvest of one male and one adult female every year would result in the population going extinct within 78 years. The time to carrying capacity of 100 years is the result of the high mortality rate experienced by this population. Loss of genetic diversity will be greater if the population remains low or well below carrying capacity rather than if allowed to reach carrying capacity. Results suggest that long-term survival, in the absence of poaching, is primarily limited by the carrying capacity of Dazhaizi. Therefore, protection of this population of black crested gibbon is dependent on the prevention of poaching and a reduction or complete cessation of habitat loss. One important step in reducing habitat loss promoting forest regeneration will be to restrict domestic animals in the habitat of black crested gibbon. In addition it will be crucial to protect and improve corridors connecting this population to surrounding populations.