The process of adaptation for extrauterine life can be easily disturbed by respiratory insufficiency. The surfactant deficiency as well as anatomical and physiological immaturity of a newborn can be considered as etiological factors in some diseases, such as respiratory distress syndrome (RDS), transient tachypnoea (TT) syndrome, segmental atelectasis or pneumonia complicated by atelectasis. The widespread used method of treatment is based on mechanical increase of difference between alveolar and atmospheric pressure. So-called constant distending pressure (CDP) increases functional residual capacity (FRC), keeps alveoli open and finally increases oxygenation of arterial blood. During 3 years period continuous positive airway pressure by nasal route (n-CPAP) was used as only one method in 26 newborns. The newborns were treated because of RDS (15 cases) and pneumonia with atelectasis (11 cases). n-CPAP was starting with pressure 8 cm H2O (0.8 kPa) and FIO2 0.5, if atelectasis with severe dyspnea, hypoxia and forced hyperventilation were found. This method was very well tolerated. 22 newborns treated for 2-7 days--survived, 4 small-for-date babies--died. The most common cause of death was septicaemia complicated by disseminated intravascular coagulation. The moderate hyperbilirubinemia, oliguria with tissue oedema was observed in many cases. The light nostril decubitus were only complications. No pneumothorax was detected. We found n-CPAP as a simple, safe method in treatment of atelectasis in newborns.