We studied the spatial distribution pattern of cereal aphids along with the dynamic tracking of aphid parasite, in Zhongning County, which would provide scientific basis for comprehending the occurrence regularity and prevention of the aphids in arid area of northwest district. Employing the checkerboard-type investigation in 5 places, we analyzed and simulated the distribution and temporal dynamics of aphids and its parasite with aggregation indices and gray relational degree in different landscape structures. There were 10 kinds of Aphidiidae and 1 kind of Aphelinidae in the local field. The population of cereal aphids (Sitobion avenae,Schizaphis graminum) and the parasites mainly showed aggregation distribution, fitting the negative binomial distribution. The aggregation distribution indices increased along with the increasing of the density itself. The aggregate of S. avenae other than S. graminum was affected remarkably by the complexity of field. The spatial patterns of the aphids changed periodically from diffusion to assembly. The distribution of the parasite was related to the aphids densities, and the tracking effect to S. avenae was stronger than to S. graminum. When tested by Blackith’s method, the aggregation was induced by environmental factors, such as climate, growth period and so on, and if the density of S. avenae and S. graminum was more than 5.57 and 8.26, per plant respectively, the aggregation depended on the interaction between the creature themselves and the environment. Aphidius avenae, A. gifuensis and A. sichuanensis had significant trace relationships with the aphid populations.