Limited information is available on anticoagulant-related nephropathy (ARN). We therefore reviewed the Japanese Adverse Drug Event Report database to investigate kidney injury (KI) in patients administered warfarin or direct oral anticoagulants (DOACs) and sought to clarify the risk factors for ARN. KI risk in warfarin users was associated with male sex (odds ratio [OR], 1.70; 95% confidence interval [CI], 1.35-2.13; P < .01) and age ≥80 years (OR, 1.35; 95% CI, 1.07-1.72; P = .01). KI risk in DOAC users was associated with body weight ≥80 kg (OR, 1.60; 95% CI, 1.01-2.53; P = .04) and use of dabigatran (OR, 1.61; 95% CI, 1.09-2.37; P < .01). Our findings suggest that risk factors for ARN differ between warfarin and DOACs and that these risk factors may be associated with bleeding risk. Therefore, the risk of ARN may be decreased by better managing bleeding risk in patients taking anticoagulants.