Abstract: Based on the structural similarity between acyl homoserine lactones (AHLs) and N-Cbz-L-homoserine lactones, the promotion of styrene biodegradation by the addition of N-Cbz-L-homoserine lactones was investigated in this study. Meanwhile, an efficient qualitative method was designed to detect small amounts of AHLs secreted by the strains in a biotrickling filter (BTF). After processing the filler in the BTF, the indicator bacteria and the reaction precursor 5-bromo-4-chloro-3-indolyl-β-D-galactopyranoside (X-gal) needed to be injected to react with the AHLs for a color development reaction. X-gal did not require membrane filtration to remove the bacteria. The addition of gentamicin sulfate at a mass concentration of 30 μg/mL could inhibit the heterobacteria introduced by X-gal without any toxic effects on the indicator bacteria. Both the plate punch assay and the streaking assay are suitable for qualitatively detecting AHLs, with the punch assay being more suitable for quantitative detection. N-Cbz-L-homoserine lactone has a similar structure to AHLs. The test proved that it can induce Agrobacterium tumefaciens to decompose X-gal in the medium, causing the expression of the substrate in a blue color, which exhibits characteristics similar to AHLs and has been confirmed as one of the signaling molecules of Gram-negative bacteria. The test results indicated that the addition of a certain concentration of N-Cbz-L-homoserine lactone enhanced the efficiency of styrene degradation. The degradation efficiency of styrene increased by up to 27.9% with the addition of N-Cbz-L-homoserine lactone at a mass concentration of 0.033 mg/mL, and by up to 21.8% with the addition of N-Cbz-L-homoserine lactone at a mass concentration of 0.133 mg/mL. This addition had significantly promoted effect on the degradation of styrene. Additionally, the addition of two concentrations of N-Cbz-L-homoserine reduced the time for complete styrene degradation by 20% compared to the control group, which verified that N-Cbz-L-homoserine lactone indirectly enhanced the activity of styrene-degrading bacteria by activating the mechanism of group sensing effect, thereby improving the efficiency of styrene degradation.