Resumen: Coronavirus infection has been the cause of millions of deaths worldwide. Some analytical parameters on admission could help predict prognosis and mortality. This study aims to describe the main Laboratory findings of hospitalized patients with COVID-19 and to identify the relationship between intensive care unit access, length of stay and in-hospital mortality. Methods: A retrospective cohort study was performed. Demographic and analytical variables of all patients diagnosed with COVID-19 hospitalized in Aragon (Spain) between March and June 2020 were analyzed. Results: We describe the characteristics of 2640 patients hospitalized with COVID-19, 85% were significantly older, with a median age of 72.3 ± 16.7 years, predominantly male (52.8%). The in-hospital mortality rate was 30%. Patients admitted to the intensive care unit had significantly higher baseline levels of hematocrit, fibrinogen, lactate dehydrogenase, leukocytes and neutrophils (p<0.001 in all). On the other hand, these patients had lower levels of eosinophils, lymphocytes and monocytes (p<0.001 in all). Only hemoglobin and D-dimer showed a significant and positive correlation with longer hospital and ICU stays (r=0.050 with p=0.031; r=0.203 with p=0.008; r=0.175 with p<0.001 and r=0.199 with p=0.001, respectively. Multivariable regression based on death showed that age, higher values of lactate dehydrogenase, neutrophils and lower values of eosinophils and female sex could explain up to 30% of the probability of death. Conclusion: Laboratory parameters can help clinicians predict the severity of COVID-19 and subsequently improve prognosis and decrease mortality rates. However, more studies are needed to better understand these changes and their relationship to prognosis. Idioma: Inglés DOI: 10.31488/EJRM.136 Año: 2022 Publicado en: European journal of respiratory medicine 4, 3 (2022), 344-341 ISSN: 2633-7452 Financiación: info:eu-repo/grantAgreement/ES/DGA/B21-20R Tipo y forma: Artículo (Versión definitiva) Área (Departamento): Área Psicología Social (Dpto. Psicología y Sociología) Área (Departamento): Area Medicina (Dpto. Medicina, Psiqu. y Derm.)