Covid-19 is a disease that affects the whole world and often causes the death of hundreds of thousands of people with lung involvement. In recent years, it is an unprecedented reason for occupancy in hospital wards and intensive care units. In this study, it was aimed to compare the lung dynamics, prognosis, and mortality of vaccinated and unvaccinated patients in the intensive care unit. Patients hospitalized in Intensive Care Units between August 1, 2021 and September 30, 2021 were retrospectively examined. A total of 197 vaccinated and unvaccinated patients over 18 years of age, with positive PCR tests, and hospitalized in the intensive care unit were included in the study. Age, gender, comorbidity, vaccination, oxygen support, mechanical ventilator parameters, intubation times, radiology data and mortality of the patients included in the study were examined. According to our study, Covid-19 disease is more common in male gender, patients over 65 years of age and those with comorbidities. Unvaccinated patients are 4 times more than vaccinated patients in intensive care. Almost all patients need oxygen support, but intubation is more common in unvaccinated patients. Mortality rates in the intensive care unit; it was found in 18% vaccinated patients, 64% unvaccinated patients, 53.8% overall. The most common causes of mortality were ARDS and sepsis. Severe ARDS is more common to unvaccinated patients. Lung dynamic compliance <18 mL/cmH2O is associated with mortality. Severe lung damage on CT score is associated with ARDS and mortality. Mortality is more common to unvaccinated patients.