Background: The use of Insecticide-Treated Nets (ITNs) is recognised as an important method in the prevention of malaria. The universal access policy has led to high levels of ITN ownership across different socio-economic groups. Despite this, recent surveys show that the age group 5-19 year olds are the least likely to use ITNs in households with ITNs. Therefore, this study aims at identifying factors associated with low ITN utilisation in this age group. Methods: Data stem from the Malaria Indicator Survey 2010 which covered the entire Zambia was used. Of the total number of 5-19 year olds (n=7 429), only 65% (n=4810) met the inclusion criteria for this study. Variables were derived from the questionnaire answered by household heads. Chi square was used to establish the association of each variable with sleeping under ITN a night before the survey. Those with p value<0.05 were retained and included in the multivariate logistic regression to come up with the final model. Results: The ITN utilisation among the 5-19 year old individuals from households with the head having primary and secondary education were not statistically significant from those who came from households where the head had never been to school. However, those who came from households with the head having tertiary education attainment were more likely to sleep under an ITN a night before the survey than those from households headed by individuals who never attended school (OR=1.79; 95% CI, 1.19-2.41). The number of ITNs in households was also an important determinant of ITN utilisation. Those who came from households with two ITNs were more likely to use ITNs than those from households with only one ITN (OR=3.93; 95% CI 3.01-5.13) and those from households with three or more ITNs were more likely to use ITNs than those from households with one ITN (OR=5.10; 95% CI 3.61-7.19). Females were also more likely to use ITNs than males (OR=1.36; 95% CI 1.17-1.58). Conclusion: The findings suggest that tertiary education of the head of the household and number of ITNs is important in determining ITN utilisation by 5-19 year olds. Therefore, reaching universal coverage on ITNs accompanied by health education especially targeting those with lower education levels could lead to equity of utilisation across all age groups.