Abstract: Objective：To explore the toxic effect and metabolic mechanism of Pseudomonas aeruginosa on edlworm by investigating the effect of Pseudomonas aeruginosa in different culture media on the development and reproduction of Caenorhabditis elegans (C. elegans), and observing the changes of cyp35 family genes expressions. Methods：The C. elegans model infected by Pseudomonas aeruginosa was established. Then, the C. elegans were cultured in LB, TSA, PGS and PGA media, respectively, and its lifespan, appearance, egglaying and movement were observed. The expressions of cyp35 family genes including cyp35A1, cyp35A2, cyp35 A5 and cyp35C1 were detected by RT-PCR. Results：The C. elegans infected by Pseudomonas aeruginosa showed retardant growth and development, and slow movement. The average survival time and egglaying number of C. elegans in LB, TSA, PGS and PGA media were significantly lower than that in nematode growth medium (NGM) (P<0.05). The expression levels of cyp35A1, cyp35A2, cyp35A5 and cyp35C1 in the C. elegans infected by Pseudomonas aeruginosa increased significantly (P<0.05). Conclusion：Pseudomonas aeruginosa in different culture media has different toxic effects on C.elegans, and the toxin metabolism in C.elegans is closely related to cyp35 family genes.