Objectives: To evaluate the prevalence and demographic factors associated with worm medication use among preschool children in Nigerian. Method: The study was based on data drawn from the Nigeria Demographic and Health Survey (NDHS) 2008 on the administration of worm medicines within six months preceding the survey. A total of 22,100 children between 6-59 months were included in the study. The chi square test for independence was performed to determine association between de-worming and demographic variables. Results: The prevalence of worm medication use among preschool children was 21.3% (95% Confidence Interval of 20.8 % – 21.8%). Worm medication use was found to be significantly associated (P < 0.05) with child’s age, child’s residence, geographical zone, mother’s education, mother’s age at birth, and wealth quintile. There was no association between worm medication use and the sex of a child. Worm medication use was found to be high in urban children and children in the southern part of Nigeria. Conclusion: The use of worm medications in preschool children in Nigeria is low. There is need for health education on the importance of de-worming among high risks group and the implementation of a national de-worming programme for preschool children.