Objective To explore the protective effect of curcumin ( Cur) on acute renal injury caused by pregnancy-induced hypertension ( PIH) and to explore the mechanism of any effect. Methods Thirty-two pregnant Sprague-Dawley female rats were divided into four groups: normal, curcumin, PIH, and PIH + curcumin groups. Rats in the PIH and PIH + curcumin groups were injected with 26 mol / L NG-nitro-L-arginine methyl ester every day for 4 days to induce PIH. The rats in the curcumin and PIH + curcumin groups were fed curcumin 204. 8 mol / L ( suspended in 2% carboxymethyl cellulose solution) from day 18 for 7 days. Hematoxylin-eosin staining, enzyme-linked immunosorbent assays and spectrophotometry were used to detect a series of indicators to evaluate the pathological morphology of kidney tissue, renal function, oxidative stress and inflammation. Immunohistochemistry and Western blot were used to detect the expression levels and distribution of TGF-β1 and p-SMAD3. Results Compared with the PIH group, the renal function of rats in the PIH + curcumin group was significantly improved (P<0. 01), and renal tissue damage and oxidative stress were also significantly reduced (P<0. 01). The renal tissue score decreased from 191. 23±18. 82 to 108. 35±11. 24 (P<0. 01). Levels of TGF-β1 and p-SMAD3 in the kidneys of PIH group rats were significantly increased, but decreased significantly after the application of curcumin. The expression of TGF-β1 decreased from (356. 25±40. 13)% to (178. 40±18. 45)% (P<0. 01). p-SMAD3 / SMAD3 decreased from (312. 82±30. 26)% to (143. 05±15. 31)% (P<0. 01). Conclusions Curcumin can protect against acute kidney injury in pregnant hypertensive rats by regulating the TGF-β1 pathway.