Chimeric antigen receptor (CAR) T cells targeting CD19 induce durable remissions in patients with relapsed or refractory non-Hodgkin lymphoma (NHL), but many patients experience treatment-related toxicity. Cytokine release syndrome and immune effector cell-associated neurologic syndrome are extensively characterized. However, limited data exist on the burden, predictors, and implications of acute kidney injury (AKI) after CAR T-cell therapy. On initial screening of the Food and Drug Administration adverse event reporting system, we identified a disproportionately high rate of renal adverse events among nearly 6,000 CAR T adverse event reports, suggesting it is clinically important in this patient population. In a subsequent single-center analysis of 399 NHL patients treated with CD19 CAR T cells, we found a substantial burden of AKI after CAR T infusion (10% and 5% of any grade and grade ≥2 AKI) with pre-renal causes being predominant (72%). Evolution to chronic kidney disease was rare, however, three patients required hemodialysis. Importantly, patients experiencing cytokine release syndrome and/or neurotoxicity as well as those with low serum albumin and high inflammatory cytokines, including IL-6 and TNF-α, were more likely to develop AKI. While pre-CAR T renal dysfunction was not associated with adverse outcomes, patients developing post-CAR T AKI had lower overall survival compared to their counterparts. Our findings indicate that renal dysfunction is a common toxicity of CAR T-cell therapy with meaningful prognostic impact. Notably, the link between systemic inflammation and renal dysfunction, suggests that readily available biomarkers may inform on renal injury risk after CAR T-cell therapy.