<b>Objective:</b> This study aimed to investigate whether pomolic acid (PA), a predicted bioactive metabolite of the Dong botanical drug Madeng'ai (MDA), suppresses inflammatory cytokine expression by inhibiting nuclear factor-κB (NF-κB) pathway activation in a tumor necrosis factor-α (TNF-α)-induced human rheumatoid arthritis fibroblast-like synoviocyte (RA-HFLS) model. Here, NFKB1 is linked to rheumatoid arthritis.