In the consecutive 2-year field study (2007~2008), we took soil samples at four different cotton growth stages, namely, seedling, budding, boll forming and boll opening stages from cotton fields that had been planted with Cry1Ac cottons separately since 1999, 2002 and 2006, and collected soil meso- and microarthropodas in the samples with the modified Tullgren method, to monitor environmental impact of long-term cultivation of transgenic insect-resistant cotton in field conditions. A total of 12 taxonomic groups of soil meso- and microarthropods were obtained from soil samples collected in 8 times during the 2 years and could be further sorted into 7 classes, and 11 orders under arthropodas phyla. Collembola, Opisthopora and Acarina were the dominant groups and Symphyla, Isoptera, Hemiptera, Diplura, Coleoptera and Homoptera were the common groups in the soil. The Generalized Linear Mixed Model (GLMM) analysis of the 2-year data on soil arthropods shows that no significant difference was found between cotton fields different in cultivation age in individual number and the community diversity indices of the soil meso- and microarthropodas of the main soil arthropod groups, but significant seasonal variation was observed of the individual numbers and the diversity indices of the main soil meso- and microarthropodas. The Principal Component Analysis suggested that Collembola, Opisthopora and Acarina were relatively higher in value and can be cited as important indicator organisms to monitor environmental impacts of transgenic plants in the future in this region.