Abstract: The landscape change is one of the main driving forces that affect the ecological environment change. And different landscape process depends on the different landscape pattern. The quantitative research of landscape change using the landscape indexes helps in revealing the landscape patches heterogeneity and ecological process. The quantitative research of landscape pattern on the basis of dynamic monitoring on the landscape structure can reveal the characteristics of landscape change and driving force in order to guide the work of landscape planning and environmental protection. With the development of geographical information system and remote sensing technique，more and more new methods based on these new technique are produced，which opens up new avenues for researchers to carry out in-depth study on the field of landscape change. The arid area is a strangely influenced region by human activities and the ecology is sensitive and vulnerable there. The fragility of its nature environment is affected synthetically by physical factor and artificial factor. With the interaction of all the factors，the fragility environment may be changing towards an unfavourable direction for resource utilization by human. Shapotou is located in arid region of northwest China，which has a fragile ecological environment. Since its establishment，the Shapotou Nature Reserve has been developing the ecological construction with the integration between developing production and maintaining ecological balance. While production activities in the Shapotou Nature Reserve positively imapct on ecological environment. Therefore further study on the ecotope topic of this reserve with fragile ecological environment and intense interfere of human beings will be scientifically and practically meaningful. Above all，based on the TM images in 1990，1996，2007 and 2011 and the ETM+ image in 2002，the changes of landscape structure and landscape patterns were analyzed in the Shapotou Natute Reserve. The research on the changing characteristics of landscape structure mainly depends on dynamic degree model and transition matrix. And the study on the landscape pattern character changes of the Shapotou Natute Reserve relied on landscape index，which is supported by GIS and landscape analysis software FRAGSTATES. Based on the reference landscape classification results at home and abroad，combined with landscape characteristic of the research area，the landscapes were classified. The results show that landscape changed significantly from 1990 to 2011. The area of farmland，timber forest，waters and construction land increased and that of grassland and desert decreased. Meanwhile the area of shelter forest and desert grassland fluctuated. The major patterns of landscape change were the conversions from desert and grassland to farmland，timber forest and water body. And there is three reciprocal transformation among shelter forest，desert and desert grassland. The dynamic degree of landscape increasing year by year indicates that the intensity of human disturbance increased. The analysis of landscape index showed that landscape diversity index，patch irregular degree and patch dispersion increased from 1990 to 2007. While，after 2007，there is a transformation of regional dominant landscape from desert to timber tree. And landscape diversity index，patch irregular degree and patch dispersion decreased.

Key words: landscape structure, landscape pattern, the Shapotou Nature Reserve