Evaluation of spatial accessibility are always the research hotspot in space planning, geography and so on. This article makes full use of two GIS-based accessibility measures including the two-step floating catchment area method and the gravity-based method to examining spatial accessibility to town and rural in Dachang County. Based on communicant and socioeconomic data of Dachang County in 2009, the paper assesses the variation of spatial accessibility to town and rural in Dachang County, and analyzes the sensitivity of results by experimenting with ranges of threshold travel times in the two-step floating catchment area method and travel friction coefficients in the gravity model, and so as to provide the scientific references for the planning distribution of public facilities in the county.