Injuries are important causes of death and disability. The purpose of this study was to determine how often preschoolers have injuries and what factors affect the injury occurrences. The sample consisted of 360 preschoolers who were registered at eight nurseries located in Sedaemoongu, Seoul. The data were analyzed using the SAS PC statistical package. The results of the study are as follows: During last 12 months 73.1% of 360 preschoolers had accidental injuries. In an analysis of the location where the injury took place, showed that the most places were in the nursery(17.3%) and around home(14.4%), and the most place inside home were in the bedroom(13.9%) and living room(13.9%). There were the diverse and injurious risks inside the home as well as around home. The most frequent type of injury was abrasion(27.5%) and most children injured their legs(28.3%). They were treated most frequently at home(52.8%) and usually emergency treatment was performed by family members with disinfection being the main type of first aid. To identify factors related to injury occurrence, multiple logistic regression was performed and the main factors were the age of child, active tendency, and mother's education level.