Based on 3S technology, the MSS image in 1973 and the TM image in 1999 were used to study the characteristics of the spatial-temporal changes of the habitat, and approached the effects of the changes on Trachypithecus leucocephalus after the changes. The results indicated that the landscape pattern of the habitats used by T. leucocephalus changed dramatically within 26 years. The mean patches area and Contagion index decreased to 34.89% and 12.23% respectively, and Landscape diversity index, landscape shape index, edge density index, fragmentation index increased to 14.15%, 3108%, 36.39%, 64.17% respectively; the area of forest patches which are important to T. leucocephalus decreased to 18`50%, but the artificial landscape such as farmland and village greatly increased. The great changes of the landscape pattern and the depravation of the habitats would cause the harm to the survival of T. leucocephalus.