Baicalin　and　baicalein　are　flavonoid　compounds　derived　from　Scutellaria　baicalensis　Georgi.　These　compounds　have　been　used　in　the　treatment　of　numerous　diseases,　including　fibrotic　diseases.　However,　research　regarding　their　antifibrotic　effects　and　mechanism　of　action　in　renal　fibrosis　is　limited.　In　the　present　study,　normal　rat　kidney　interstitial　fibroblast　(NRK-49F)　cells　were　stimulated　with　transforming　growth　factor　(TGF)-beta　1,　with　or　without　baicalin/baicalein,　and　assessed　for　proliferation,　apoptosis,　extracellular　matrix　(ECM)　accumulation,　collagen　expression,　TGF-beta　1　expression　and　mothers　against　decapentaplegic　homolog　3　(SMAD3)　protein　activation.　The　results　revealed　that　baicalin　and　baicalein　exhibited　antifibrotic　effects　in　vitro,　whereas　baicalein　had　a　stronger　inhibitory　action　compared　with　baicalin　on　TGF-beta　1-induced　NRK-49F　cell　proliferation,　deposition　of　ECM,　collagen　synthesis,　endogenous　TGF-beta　1　expression　and　phosphorylation　of　SMAD3.　In　conclusion,　the　findings　of　the　present　study　indicate　that　baicalin　and　baicalein,　particularly　baicalein,　exhibit　antifibrotic　effects　in　vitro　by　inhibiting　the　TGF-beta　1　pathway.　Therefore,　these　compounds　have　the　potential　to　be　developed　as　novel　agents　to　treat　renal　fibrosis.