Objective To investigate the clinical effect and nursing experience of Yakult in preventing enteral nutrition related diarrhea of mechanically ventilated patients.Methods 70 mechanically ventilated patients underwent nasogastric enteral nutrition in ICU of our hospital from 2010 to 2012 were randomly divided into observation group and control group.Control group received conventional enteral nutrition (EN),while observation group received Yakult on the basis of conventional EN.Observed and compared the curative effect of two groups,and strengthened nursing care in two groups.Result The incidence of diarrhea in observation group was significantly lower than that in control group (11.4% vs.37.1%),with statistically significant difference (P < 0.05).Conclusions Yakult is very effective in preventing enteral nutrition related diarrhea of mechanically ventilated patients,can significantly reduce the incidence of diarrhea.Nursing care should he strengthened in order to promote the recovery and improve the prognosis of patients. Key words: Yakult; Mechanical ventilation; Enteral nutrition; Diarrhea; Nursing care