The aim of this study was to analyze the general characteristics of children in the pediatric emergency department (PED) who accidentally fall off the crib and to establish useful preventive measures. This prospective research analyzed pediatric patients who accidentally fell off their beds in the observational unit (OU) of the PED from July 2005 to June 2006 (first period). From July 2006 to February 2007 (second period), the causes of children falling off the crib in the first year were analyzed and five related preventive methods were instituted in the OU. From July 2007 to March 2008 (third period), the preventive methods were enhanced to achieve zero-event of accidental falls in the PED. The differences between patients falling off the bed among the three periods were then compared. This study collected 7,281 children admitted to the OU during the first period and recorded 15 cases of accidental falls. After performing the preventive methods in 6,232 patients in the second period, three events of accidental falls were noted. In the third period, there was no accident in the 5,225 patients admitted to the PED. Comparing the occurrences of children falling off the bed among the three periods, accidental falls significantly decreased in the third period (p < 0.001). Effective methods can be instituted to prevent children from falling off the bed, especially in the PED.