A bacterial strain capable of utilizing only butachlor as carbon source, named C–5, was isolated from butachlor-contaminated soil in sewage outfalls and waste reservoirs of several pesticide factories using enrichment culture technique. Strain C–5 was identified as Delftia sp. based on its morphological, physiological and biochemical characteristics and on 16S rDNA homologue sequence analysis. The optimal pH value and temperature for growth of strain C–5 were 7.0 and 30℃, respectively. When the initial mass concentration of butachlor was 20 mg/L and the inoculation rate of strain C–5 (OD600 nm=1.34) was 5%, more than 76% of butachlor was degraded. When inoculation rate of strain C–5 was 10% and the seedlings were treated with butachlor in mass concentration of 5 mg/L, the emergence rate reached 87%, only 10% lower compared to the blank control, while 50% higher compared to the group without inoculation of strain C–5；the plant height was 44% lower than the blank control, but 93% higher than the group without inoculation of strain C–5 under laboratory conditions. Analyses of the emergence rate and the plant height of rice seedlings indicated that bioremediation effect of strain C–5 was over 50%.