First, the result of network pharmacology identified 10 potential targets, such as GBA, GSR, MC4R, MMP2, MMP9, NFKB1, RELA, NR1I2, PPARD, and CRABP2, of fucoidan against PFOA-associated obesity. The gene discussed is MMP9; the disease is obesity due to melanocortin 4 receptor deficiency.