SARS-CoV-2 virus has caused a pandemic of COVID-19 disease that has spread to almost entire world in a short period of time and has caused a crisis in the healthcare system around the world. Numerous data obtained from research have indicated that patients with cancer, and especially with malignant hematological diseases, have a significantly higher incidence of severe symptoms and outcomes after infection with the virus. The aim of this study was to describe the differences in age parameters and comorbidities in hematological and non-hematological patients with COVID-19 infection. We assumed that there will be a statistically significant difference in the frequencies of patients on respirator and high flow between hematological and non-hematological patients, and such that statistically significantly more people will be on respirator and high flow if they are hematological patients. We also assumed that there would be a statistically significant difference in the frequencies of deceased hematological patients from the frequency of deceased non-hematological patients, and such that the frequency of hematological patients would be statistically significantly higher than the frequency of non-hematological patients. As a measuring instrument was used a computer database (BIS). The results suggest that hematological patients are more prone to developing severe forms of the disease, and the cause may be primary malignancy, as well as eventual treatment that often contains aggressive cytostatics. Severe forms of the disease require both, a treatment process and long-term recovery, so that in hematological patients there is a greater need for a high flow (HF) device and respirator. Also, in our study, a higher mortality rate was observed in hematological patients compared to non-hematological ones. In order to discover the exact causes, additional scientific research are needed.