BACKGROUND: Coronavirus disease 2019 (COVID-19) and cancer are serious public health problems worldwide. However, little is known about the risk factors of in-hospital mortality among COVID-19 patients with and without cancer in Brazil. The objective of this study was to evaluate the risk factors of in-hospital mortality among COVID-19 patients with and without cancer and to compare mortality according to gender and topography during the year 2020 in Brazil. METHODS: This was a secondary data study of hospitalized adult patients with a diagnosis of COVID-19 by real-time polymerase chain reaction testing in Brazil. The data were collected from the Influenza Epidemiological Surveillance Information System. RESULTS: This study analyzed data from 322,817 patients. The prevalence of cancer in patients with COVID-19 was 2.3%. COVID-19 patients with neurological diseases and cancer had the most lethal comorbidities in both sexes. COVID-19 patients with cancer were more likely to be older (median age, 67 vs 62 years; P < .001), to have a longer hospital stay (13.1 vs 11.5 days; P < .001), to be admitted to the intensive care unit (45.3% vs 39.6%; P < .001), to receive more invasive mechanical ventilation (27.1% vs 21.9%), and to have a higher risk of death (adjusted odds ratio [aOR], 1.94; 95% confidence interval [CI], 1.83-2.06; P < .001) than those without cancer. Patients with hematological neoplasia (aOR, 2.85; 95% CI, 2.41-3.38; P < .001) had a higher risk of mortality than those with solid tumors (aOR, 1.83; 95% CI, 1.72-1.95; P < .001) in both sexes. CONCLUSIONS: Brazilian COVID-19 patients with cancer have higher disease severity and a higher risk of mortality than those without cancer.