An experiment was conducted in lab by inoculating cypermethrin-contaminated soil,separately,with cypermethrin,3-Phenoxybenzoic acid (3-PBA)-degrading bacteria CDT3 (Rhodoccus sp.) and PBM11 (Pesudomonas sp.) to study their effects on microbial remediation of the contaminated soil and soil microbial communities.Samples were collected from the inoculated soils and CK (uninoculated) on D0,D3,D7,D15,and D30 for analysis of residues of cypermethrin and 3-Phenoxybenzoic acid (3-PBA) in the soil as well as monitoring of dynamics of the microbial communities in the soil,using the plate counting method and denaturing gradientgel electrophoresis(DGGE) method.The analysis results show that the cooperation of CDT3 and PBM11 promoted the degradation of cypermethrin and its metabolite 3-PBA in the soil.As cypermethrin inhibits significantly native edaphon in soil,inoculation of these degrading-bacteria could eliminate the inhibitive effect of cypermethrin on edaphon,thus promoting restoration of indigenous microbial population and communities.But it could not be expected that the damage cypermethrin brings to the soil microbial structure could be removed within a short period of time.