ABSTRACT:The effects of urinary‐tract obstruction on renal function have been clarified. However, there is little known about the change of renal vitamin D metabolic enzyme expression and vitamin D‐dependent calcium transporting proteins expression in obstructive nephropathy. The male mice were subjected to unilateral ureteral obstruction (n = 10) or sham operation (n = 10). All mice were killed on day 7 after the surgical operation. Kidney sections were stained with Masson's trichrome and gene expression was analyzed by reverse transcription‐polymerase chain reaction (RT‐PCR) and real‐time PCR. The obstructed kidney exhibited interstitial fibrosis as shown by the strong collagen deposition in the interstitium. Quantitative PCR results showed the increase of 1‐OHase (P < 0.001) mRNA expression and the decrease of 24‐OHase (P < 0.01), CaBP‐9k (P < 0.01) and CaBP‐28k (P < 0.01) mRNA expression in obstructed kidney as compared to that of the Sham group. In addition, the mRNA expression of 1‐OHase and CaBP‐9k was significantly increased and decreased, respectively, in obstructed kidney as compared to that of the contra‐lateral kidney in unilateral ureteral obstruction (UUO) mice. Together, the present finding supports the hypothesis that the ureteral obstruction leads to the alteration of renal vitamin D metabolic enzyme expression and calcium transporter abundance, which may secondarily induce the abnormality of vitamin D endocrine system and bone health.