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The effect of carbendazim applications on the diversity and structure of a soil bacterial community was studied under field conditions using temperature gradient gel electrophoresis (TGGE) and partial sequence analysis of PCR-amplified 16S a gene. After four successive Introductions of carbendazim at a level of 0.94 kg active ingredient (a.I.)/ha, the genetic diversity (expressed as Shannon index, H’) decreased from 1.43 in the control to 1.29 in treated soil. This harmful effect seems to increase with the concentration of carbendazim. The value of H’ in the soil treated with carbendazim at 4.70 kg a.I./ha was reduced to 1.05 (P ≤ 0.05). The soil bacterial community structure was also affected after four repeated applications of carbendazim at levels of 0.94, 1.88 and 4.70 kg a.I./ha, as seen in the relative intensities of the individual bands. However, the bacterial community in carbendazim-treated soil recovered to that in the control 315 d after the fourth treatment. The results indicate that repeated applications of carbendazim could reduce soil microbial diversity and alter the bacterial community structure temporarily.