Objective To study the influence of the supine or the prone position on the lung function in the neonates with pneumonia in order to find a suitable position for neonates with pneumonia. Methods Respiratory rate, tidal volume, minute ventilation, airway resistance, dynamic pulmonary compliance and work of breathing in the supine or prone position were measured by American Biocore CP-100 Neonatal Pulmonary Apparatus in 30 neonates with pneumonia. Results Respiratory rate ( 44.3± 9.2 bpm/min) and airway resistance [( 153.1± 50.4) cmH 2O/(L.sec)] in neonates with a prone position were significantly lower than those in the supine position [( 48.0± 10.6 bpm/min) and ( 211.9± 63.1) cmH 2O/(L.sec), respectively] (P< 0.01). Tidal volume ( 2.29± 0.46 ml/kg), minute ventilation [( 0.095± 0.024) L/(min.kg)], dynamic pulmonary compliance [( 0.621± 0.214) ml/(cmH 2O.kg)] and work of breathing ( 8.9± 3.5) gm/(cm.kg)] in the prone position were significantly higher than those in the supine position [( 1.65± 0.50 ml/kg), ( 0.075± 0.022) L/(min.kg), ( 0.389± 0.115) ml/(cmH 2O.kg) and ( 5.9± 2.7) gm/(cm.kg), respectively] (P< 0.01). Conclusions A prone position may increase the tidal volume, minute ventilation and dynamic pulmonary compliance and decrease respiratory rate and airway resistance. It suggests that a prone position is the suitable one for neonates with pneumonia.