PPHN is a life threatening disease that appears as a result of high pulmonary vascular resistance and persistent right to left shunt across foramen ovale and ductus arteriosus. The treatment of PPHN is complex and often ineffective. iNO is important part of the pathogenetic treatment of the disease. We present six infants with PPHN treated with iNO. The clinical effect of the drug was quick and the hemodynamics stabilized. All infants survived without side effects and with better neurodevelopment outcome.