Landscape pattern is the arrangement of landscape embedded blocks of different sizes and shapes. Landscape pattern changes result from complex interactions of physical, biological and social forces. Human land use has influenced most landscapes, resulting in a landscape mosaic of natural and human-managed patches that vary in size, shape and arrangement. The quantitative analysis of landscape pattern is the fundamental of researching the mutual relations of landscape patterns and ecological processes. Loess Plateau is one of the world's largest loess areas with a long history of human activities, and the natural environment is fragile. Research on Landscape pattern evolution in the hilly and gully area of Loess Plateau has long been a research hotspot. The analysis of landscape pattern changes in Loess Plateau has a crucial role in understanding the structure and changes of the ecosystem. This study analyzed the evolution characteristic of landscape pattern and the spatial differentiation of main evolution types in Yan'an City based on landscape ecology theory, using GIS technology. 1:250000 landscape type maps in 1985, 2000 and 2008 and digital elevation model (DEM) of Yan'an City are used in this research. Considering the local characteristics and referring to domestic and foreign land use classification system, Yan'an City landscape types are divided into seven categories, namely woodland, bush, grassland, farmland, settlements, water and bare ground. Different methods such as Multi-Distance Spatial Cluster, landscape transition matrix, spatial data overlay analysis, were used in this research. The primary conclusions were as follows: the landscape background of Yan'an City is a composite landscape matrix consisting of woodland, bush, grassland and farmland. The area of farmland decreased sharply during the study period. The reduced farmland mainly transformed into forest land, grassland, bush and settlements. Other landscape types except farmland and bare land are increased at different degrees. The maximum aggregation scale of woodland, bush and grassland decreased from 1985 to 2008, while that of farmland became larger. The spatial aggregation intensity of farmland and grassland was significantly less than that of woodland and bush. The evolution of main landscape types mostly occurred at altitudes between 1100 m and 1500 m, and the gradient of slope was varied in the range from 7° to 21°. The evolution of farmland to settlement occurred mainly at altitudes between 900 m and 1300 m, and the slope was less than 7°. Yan'an City is located in Loess Plateau which is the most serious area of soil erosion in China. Therefore, the government has adopted a series of comprehensive measures to achieve the aim of effective control of soil erosion. Returning farmland to forest, re-building sloping land into level terrace and strengthening the construction of "Three North" shelterbelt are all in their implementation. Yan'an City is the political, economic and cultural center in Northern Shaanxi. The rapid socio-economic development was the main reason for the landscape patterns' evolution before 1999; while after 1999, these measures of controlling soil erosion exceed the rapid socio-economic development, which became the main factors affecting landscape pattern evolution in Yan'an City.