OBJECTIVE: To compare the clinical efficacy of imported pulmonary surfactant (PS) pig lung phospholipids injection (pig PS) and domestic cattle lung surface-active agent (cattle PS) for the treatment of neonatal respiratory distress syndrome (NRDS). METHODS: A total of 180 cases of grade IV NRDS receiving pig PS (n=90) or cattle PS treatment (n=90) were enrolled. The blood gas analysis and chest X-ray results and the incidence of complications after treatment, and hospitalization time and cost were compared between the two treatment groups. RESULTS: The efficiency rate in the pig PS group (97%) was higher than in the catle PS group (83%) (P<0.01). The cure rate in the pig PS group was also higher than in the cattle PS group (84% vs 66%; P<0.01). The incidence of pneumothorax in the pig PS group was lower than in the cattle PS group (3% vs 7%; P<0.05). The hospitalization time in the pig PS group was shorter than in the cattle PS group (21±4 days vs 23±4 days; P<0.05). There were no significant differences in the total hospitalization cost between the two groups. CONCLUSIONS: Pig PS seems to be superior to cattle PS in the treatment of grade IV NRDS.