Pyrazosulfuron-ethyl (PSE) is a widely used herbicide for weed control. However, its persistence in soil poses risks to sensitive crops due to its long half-life. The effects of biosurfactants on microbial degradation have received widespread attention. This study investigates a newly isolated strain,    Chenggangzhangella sp. BI-1, capable of degrading PSE and explores the enhancement of its bioremediation potential using rhamnolipids (RL). Strain BI-1 effectively degraded 50 mg·L    −1 of PSE within 72 h. Notably, the hydrolase gene    pyfE was cloned, marking the first identified gene responsible for PSE degradation. The enzymatic analysis revealed that PyfE exhibited high stability and activity across a temperature range of 35–50 °C and a pH range of 7.0–8.0, with optimal degradation conditions at 40 °C and 7.5. Metal ions like Ag    + and chemical compounds like methamidophos significantly inhibited PyfE activity. HPLC-MS/MS showed that PyfE catalyzed the de-esterification of the PSE phenyl ring side chain, producing pyrazosulfuron acid. The kinetic studies showed that the    K    m of PyfE for PSE was 17.95 μM, with a    k    cat/    K    m of 0.041 s    –1 μM    –1. An enhanced bioremediation system was developed using the strain BI-1 and RL for PSE-contaminated soil. The degradation rate of PSE in soil (5 mg·kg    –1) by BI-1 strain reached 56.6 % within 10 d when treated with 100 mg·kg    –1 RL, a 1.68-fold increase compared to treatment without RL. These findings provide a theoretical basis and technical support for the bioremediation of PSE-contaminated soils.