In the model of injury and fibrosis of unilateral ureteral obstruction (UUO) mice, exogenous H2S could alleviate macrophage infiltration, tissue fibrosis, and inhibit NF-κB and IL-4/signal transducer and activator of transcription 6 (STAT6) signaling pathways and NLRP3 inflammasome, and NLRP3 inhibitor had the effect similar to that of H2S, which suggested that H2S alleviated renal fibrosis via inhibiting NLRP3 inflammasome. The gene discussed is NLRP3; the disease is renal fibrosis.