The standardized mortality ratio (SMR) is a recognized indicator of critical care quality. This ratio is used to compare actual hospital mortality of all patients treated in a Intensive Care Unit (ICU) with predicted mortality. The aim of the study was prospective analysis of SMR as a measure of quality of care in single ICU.Prospective study was performed during the period of 12 months in ICU of Czerniakowski Hospital in Warsaw. Predicted hospital mortality was calculated using the SAPS 3 model. The value of SMR was evaluated in the three risk groups (low, moderate, high risk) and included patients surgical status (nonoperative, after elective and emergency surgery).A total of 341 patients were included. SMR in general population was 0,98 (95% CI 0,74-1,28). In the low and high-risk groups the value of SMR did not differ significantly from 1. In the average risk group as well as patients undergoing elective surgery, the value of SMR tended to exceed 1.In groups of patients with low and high risk the values of SMR indicated favourable quality of care. Study results should prompt to carry out detailed analysis of the course of treatment of patients at average risk of death. Analysis of the course of treatment and qualification criteria for surgery in patients undergoing elective surgery is also indicated.