Based on the spatial and social characteristics, we classified the 155 poverty settlements in Lanzhou City into shanty-town type, urban-village type, multi-ethnic type, and single-Han-ethnic type. Then, we analyzed the spatial differentiation characteristics of poverty settlements and the impact factors using several methods such as nearest neighbor index (NNI), kernel density, buffer analysis, and overlay analysis. The results are given as follows. 1) The poverty settlements of shanty-town type, urban-village type, and single-Han-ethnic type present condensed distributions, but the multi-ethnic type presents dispersed distribution. 2) There are a high density area and a second high density area for each of the four types. There is also a third density area for each of single-Han-ethnic type and multi-ethnic type, but the central locations and the highest density values are different. 3) In terms of the spatial relations between poverty settlements and the three basic geographical elements which are the Yellow River, drainage ditches, and railways, the numbers and proportions of the four types of poverty settlements are different, and the difference of close-distant relationship is large. 4) The spatial differentiation of poverty settlements is a synergic result of several factors. At microscopic level, the natural geographical environment, historical pattern, and ethnic culture are the basic impact factors. At macroscopic level, regulation of urban planning, transformation of industrial development policy, and housing supply institution have significant influences.