Objective The purpose of this study was to investigate the relationship between VitD metabolites and their receptor levels and kidney damage in lupus nephritis (LN).Methods A total of 277 subjects who visited or underwent physical examination in Mianyang Central Hospital from April to December 2022 were selected, including 67 patients with LN (LN group), 67 patients with SLE without LN (SLE group), 68 patients with CKD caused by non-LN (non-LN-CKD group) and 75 healthy subjects (HC group). Serum VitD metabolites were detected by UPLC-MS/MS. The levels of serum VitD metabolites, VDR and kidney function indicators were compared among the groups, and the correlation between the indexes in each group and the independent risk factors affecting the occurrence of LN were analyzed. Results Compared with the HC group, the SLE group and the LN group had higher serum VDR levels, and lower serum 25(OH)D3 and C3-epi levels (all P< 0.05).In LN patients, 25(OH)D3 was positively correlated with eGFR (r＞0, P＜0.05) , with Urea, Cr, CysC and NGAL(r＜0, P＜0.05) negative correlation; C3-epi was negatively correlated with NGAL and VDR (r＜0, P＜0.05). High serum VDR and low serum C3-epi were independent risk factors for LN, and high serum 25(OH)D3 was a protective factor for LN. Conclusion The decrease of serum 25(OH)D3 and C3-epi levels and the increase of VDR level may be important pathogenic factors of LN, which play a key role in the occurrence of kidney injury in LN patients