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The contents of Cu and Ni in the topsoil, and the distribution characteristics of Cu and Ni under different parent materials and land use types were analyzed in the karst area in northern Mashan, Guangxi. The background values of Cu and Ni in the topsoil of the study area were 36. 59, 38. 82 mg / kg respectively and there were 48. 17% and 35. 96% of the samples exceeding the background values of Cu and Ni in Mashan. The relationship of Cu content in the soil was grassland>shrubland>dry farm>woodland>paddy field>orchard, and Ni was shrubland>grassland>dry farm>orchard>paddy field>woodland in different land use types. The soil-forming parent material had a significant impact on the content of soil Cu and Ni. The contents of Cu and Ni in the soil developed by carbonate rocks were significantly higher than that of clastic rocks and alluvial deposits. There were local high value regions of Cu and Ni in the area. The high value regions of Cu were mainly located in the west where human activities are single and in the east and northwest where human activities are intensive and diverse, and the distribution was relatively dispersed. The Ni high value regions were mainly located in the west and east, and the distribution was relatively concentrated. The spatial heterogeneity of Cu content is determined by both geological factors and human factors, while the spatial heterogeneity of Ni is basically derived from geological factors. The results show that the Cu and Ni contents of some samples in the study area are high, and geological factors are the main reasons for this phenomenon. The influence of soil parent material and land use on the accumulation of heavy metal elements should be fully considered when the government makes industrial and agricultural guidance planning in the research area. [ABSTRACT FROM AUTHOR]