Kidney fibrosis is considered the essential pathophysiological process for the progression of chronic kidney disease (CKD) toward renal failure. 20-Hydroxyeicosatetraenoic acid (20-HETE) has crucial roles in modulating the vascular response in the kidney and the progression of albuminuria. However, the roles of 20-HETE in kidney fibrosis are largely unexplored. In the current research, we hypothesized that if 20-HETE has important roles in the progression of kidney fibrosis, 20-HETE synthesis inhibitors might be effective against kidney fibrosis. To verify our hypothesis, this study investigated the effect of a novel and selective 20-HETE synthesis inhibitor, TP0472993, on the development of kidney fibrosis after folic acid– and obstructive-induced nephropathy in mice. Chronic treatment with TP0472993 at doses of 0.3 and 3 mg/kg twice a day attenuated the degree of kidney fibrosis in the folic acid nephropathy and the unilateral ureteral obstruction (UUO) mice, as demonstrated by reductions in Masson’s trichrome staining and the renal collagen content. In addition, TP0472993 reduced renal inflammation, as demonstrated by markedly reducing interleukin-1β (IL-1β) and tumor necrosis factor alpha (TNF-α) levels in the renal tissue. Chronic treatment with TP0472993 also reduced the activity of extracellular signal-regulated kinase 1/2 (ERK1/2) and signal transducer and activator of transcription 3 (STAT3) in the kidney of UUO mice. Our observations indicate that inhibition of 20-HETE production with TP0472993 suppresses the kidney fibrosis progression via a reduction in the ERK1/2 and STAT3 signaling pathway, suggesting that 20-HETE synthesis inhibitors might be a novel treatment option against CKD.