The present study aims to observe the effects of NCTD (norcantharidin) on proliferation and FN (fibronectin) expression in human renal proximal tubular epithelial cell line (HK-2) induced by albumin in vitro. HK-2 cells were divided into control group, albumin group and different concentration of NCTD intervention groups. Proliferation of HK-2 cells was determined by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide], FN protein in culture media of HK-2 cells was examined by ELISA, and FN mRNA was analysed by RT—PCR (reverse transcription—PCR). We chose less than 5.0 mg/l of NCTD as the experimental concentration for the cytotoxicity test. MTT score was higher in the albumin group than in the control group (P<0.05). As compared with that of the albumin group, MTT score and FN protein concentration decreased, FN mRNA significantly down-regulated in NCTD intervention groups respectively (P<0.05). Our study showed that NCTD could inhibit the albumin-induced cell proliferation and FN expression in HK-2 cells, which might further prove the anti-fibrotic role of NCTD in proteinuria-associated tubulointerstitial damage.