Abstract—The microbial population of soil is diverse and is regulated by different soil properties. This study aimed to determine the impact of climate and grazing on soil community composition in two semiarid areas, Kerman province, Iran. Soil samples were taken from four zones which were either cold or warm and either grazed by cattle or not grazed. Soil chemical analyses were determined by standard methods and the bacterial community by DNA extraction from soil followed by next generation sequencing of the 16S rRNA gene. Soil at cold areas had higher moisture, organic carbon, total nitrogen, available phosphorous and exchangeable potassium concentrations than warm sites. The abundance of Proteobacteria (28.3% ± 1.0) and Actinobacteria (44.6% ± 1.1) was highest at the cold-grazed and warm-grazed zones, respectively, which account for ~70% of all OTUs. Greater richness and evenness of bacteria at the cold areas, compared to the warm areas, was also observed and is attributed to more vegetation cover and soil organic matter, nutrient availability and moisture. There was no significant difference of chemical soil properties between the grazed and not grazed sites. However, significant differences were observed in bacterial diversity between the grazed and not grazed sites, suggesting that bacteria respond much more rapidly to grazing than to soil chemical properties. According to the Chao1 and J values, the least richness and the highest evenness belonged to the warm-grazed zone, indicating grazing had a greater effect at the warm areas, compared to the cold areas. In conclusion, change in community composition at managed (i.e. grazed versus not grazed) semiarid sites, estimated by next generation sequencing, precede detectable changes in soil chemical properties, thereby providing an early sign of change in soil quality.