The rate was lowest at 1.09% with birth weight >1500 g and rather hight (25.26%) with birth weight ≤1500 g. To decrease more the mortality rate, we should have focus on improve the weaning skills of mechanical ventilation, reduce the overload of neonatal department, strengthen Obstetric - Pediatric cooperation, as well as prevent hypothermia of LBW and VLBW infants.