Abstract: Objective To explore the predictive value of Bax inhibitor-1(BI-1)in contrastinduced nephropathy(CIN)in patients after coronary arteriography(CAG). Methods A total of 126 patients undergoing CAG were recruited from November 2020 to July 2021. General profiles, blood biochemistry and routine coagulation test were recorded. Urine samples were collected at pre-operation and 12/24/48h post-operation. Both preoperative and postoperative serum samples were assayed. BI-1level was detected by enzyme-linked immunosorbent assay(ELISA). Based upon the presence or absence of CIN, they were divided into two groups of CIN(n=14)and non-CIN(NCIN, n=112). The serum and urinary levels of BI-1 were detected. And the predictive values of serum and urine BI-1 in CIN were evaluated by receiver operating curve(ROC). Results The serum and urinary levels of BI-1 at preoperation and 12h post-operation were lower in CIN group than those in NCIN group. ROC analysis indicated that AUCs of BI-1 level of serum and urine pre/post-operation and BI-1 level of urine 12h postoperation were 0.731, 0.766 and 0.766 respectively(P<0.01). Conclusion BI-1 level of serum and urine pre/post-operation and BI-1 level of urine 12h post-operation may be employed as predictive parameters for CIN patients after CAG.