Introduction: Currently, we are facing a global pandemic COVID-19 caused by SARS-CoV-2. Since the first reported Brazilian case on February 26 to July 31 2020, Brazil has presented as the second country of the world with the highest number of cases and deaths: 2,662,485 and 92,475 respectively. Moreover, São Paulo presented the majority of Brazilian data with 542,304 cases with 22,997 deaths. We know that hematological disease are not prevalent, it is concerned to report that 1.9% of death in São Paulo presented this group of disease, according to SIVEP-Flu. Although, we understand that age and co-exisiting comorbidities such as hypertension, diabetes, obesity, chronic kidney disease are high risk factors to mortality, it was demonstrated that patients with moderate or severe COVID-19 with hematological disease have presented 28-40% of deaths. Objectives: We proposed to describe the demographic characteristics by comparing hypothetical risk factors to death, such as, age, gender, Hemato-oncology patient (HOP) versus cancer patients with Non-Hemato-Oncology cancer (NHOP) and anti-cancer therapy within 21 days before testing positive for COVID-19 in patients needed hospitalization. Methods: In this prospective observational study, On March 30 2020, we started to register all consecutive cancer patients undergoing treatment or being followed up by the Instituto Hemomed which were confirmed COVID-19 by reverse-transcriptase-polyerase-chain-reaction (RT-PCR) assay of a specimen collected on a nasopharyngeal swab between March 30 and July 31, 2020. Inclusion criteria: cancer patients, positive RT-PCR and need of hospitalization due to severe COVID-19. We excluded all patient who did not require hospitalization and patients with active case of COVID-19. Death was defined as related COVID-19 during admission as well as death reported as a consequence of any other cause during admission, such as due to cancer progression or treatment toxicity. Results: Sixty-one cases were registered until July 31, 2020, two cases were excluded with active COVID-19 and eight patients with outpatient treatment. We analyzed 51 severe COVID19 patient with cancer. Thirty-two (62.7%) sex female and median age 60 (± 17.6) years old, 31 (60.7%) HOP and 20 (39.1%) NHOP and 25(49%) were treated with anti-cancer therapy up to 21 days before COVID-19 diagnosis. Thirty (58.8%) required Intensive Care Unit (ICU), 22 (43.1%) needed invasive ventilation and 26 (51%) discharged. Twenty-five (49%) patients died - four (7.8%) of them were considered palliative care. Risk of death was age ≥ 60 years old (odds ratio 4.8 [95% CI 1.47-15.0, p = 0.008]), and anti-cancer therapy up to 21 days before COVID-19 diagnosis (odds ratio 3.4 [95% CI 1.07-10.7], p = 0.035). We found no significant effect on mortality for male (odds ratio 0.9 [95% CI 0.2-2.8, p = 0.54]) and NHOP (odds ratio 1.4 [95% CI 0.4-4.5, p = 0.34]). Conclusion: Severe COVID-19 deaths in cancer patients was 49%, more than a half of cases needed ICU and mortality appears to be related to advanced age and anti-cancer therapy up to 21 days before COVID-19.