Background: The frequency of severe chest injuries are increased. Their high morbidity is followed by systemic inflammatory response. The efficacy of pharmacological blockade of the response could prevent complications after chest injures. Aim: The aim of the study was to show an inflammatory response level, its prognostic significant and length of hospital stay after chest injures opiate analgesia treatment. Methods: Sixty patients from Department of Thoracic Surgery with severe chest injures were included in the prospective study. With respect of non opiate or opiate analgesia treatment, the patients were divided in two groups consisted of 30 patients. As a inflammatory markers, serum values of leukocytes, neutrophils, C-reactive protein (CRP) and fibrinogen in three measurements: at the time of admission, 24hours and 48 hours after admission, were followed. Results: Statistically significant differences were found between the examined groups in mean serum values of neutrophils (p=0.026 and p=0.03) in the second and the third measurement, CRP (p=0.05 and 0.25) in the second and the third measurement and leukocytes in the third measurement (p=0.016). 6 patients in group I and 3 in group II had initial stage of pneumonia, 13 patients in group I and 6 in group II had atelectasis and 7 patients from group I and 4 from group II had pleural effusion. The rate of complications was lower in group of patient who were under opiate analgesia treatment but without significant difference. The length of hospital stay for the patients in group I was 7.3±1.15 days and for the patients in group II it was 6.1±0.87 days with statistically significant difference p=0.017. Conclusion: The opiate analgesia in patients with severe chest injures reduced level of early inflammatory response, rate of intra hospital complications and length of hospital stay.