The aim of this study is to evaluate the changes of patients' satisfaction with health care services in Lithuanian Health Promoting Hospitals network. In a survey, which was carried out by Lithuanian Health Promoting Hospitals network, 1271 patients took part in 2000 and 1467 patients in 2002. The patient's satisfaction with health care services was evaluated using a uniform anonymous questionnaire. The patients were asked to evaluate hospital environment (neatness, cleanliness, and food quality), the quality of health personnel work (attentiveness, care, risk factors, and tests used for diagnosis and treatment) rating from 1 (very bad) to 6 (excellent). It was ascertained that, during the period between both surveys, the number of patients who evaluated the sanitary conditions in the ward as excellent and very good, increased from 49.2% to 59.9%, p<0.05. According to the data received from both surveys, the hospital food quality was rated more critically than the hospital environment. The number of patients, who noted that the food quality was satisfactory, decreased from 29.8% to 22.0%, p<0.05 within the period analyzed. However the number of patients who had a positive opinion of the health care personnel's attentiveness and help while explaining the causes and consequences of various illnesses increased. Patients' assessment of the physician work remained the same. The majority of the patients (95.1% in 2000 and 94.9% in 2002) appreciated the overall performance of the physicians, and rated it very good and excellent. The analysis of patients' satisfaction is a simple study of a constituent part of the health care service quality assessment and an objective prerequisite for the improvement of the quality of the health care services.