Acute tumor lysis syndrome (ATLS) caused by the destruction of malignant cells leads to metabolic abnormalities, which may either remain isolated (biological ATLS) or subsequently lead to renal dysfunction (clinical ATLS). We compared hospital and 6-month survival in patients with ATLS with hematological malignancies with or without acute renal injury. Sixty-three patients (median age, 50 years; range, 32-64) were included with ATLS. Twenty-eight had no ARI (including 17 (61%) who subsequently required dialysis) whereas 35 had an ATLS-related ARI (including 31 (89%) who required dialysis). Acute leukemia (n = 28) and lymphoma (n = 30) were the main malignancies. All patients had high tumor burdens. Hospital and 6-month mortality rates were significantly lower in patients without ARI (7% and 21%, respectively) than in the ATLS-related renal injury group (51% and 66%). After adjustment for acute disease severity, presence of ARI at ICU admission was associated with higher hospital mortality (odds ratio, 10.41; 95% confidence interval, 2.01-19.170; p = 0.005) and 6-month mortality (odds ratio, 5.61; 95% confidence interval, 1.64-54.66; p = 0.006), compared to patients without renal injury. Our study suggests that in patients with ATLS, ICU management when acute renal injury is present is associated with higher short- and long-term mortality.