Objective : Children < 15 years old are thought to be the most vulnerable group to contracting the infection than adults due to their immature or developing immunity. We investigated whether index patient child leprosy are associated with parental education, parental unemployment, parental income, household crowding, inadequate ventilation household contacts, neighbours contact and nutritional deficiency in Dili, Liquica, Manatuto, Baucau, RAEOA. Methods: We designed matched case-control study. Cases were fathers of children with leprosy under 15 years old while controls were non random sample of children without leprosy who live in the same household and neighbourhood with child leprosy < 15 years who have the same age and gender with child leprosy. The case-to-control ratio was 1:2. We identified the factors that significantly differed between the cases and controls in a multivariable binary logistic regression analysis and reported the odds ratio (OR) and 95% confidence interval (CI)Results: We found similar demographic among the 40 cases and 80 controls. The research results indicated that out of the 8 variables examined, 4 variables household contacts, household crowding, inadequate ventilation, and nutritional deficiency were significant risk factors (P value < 0.005). In a multivariate analysis, household contact was identified as a significant factor in the occurrence of leprosy in children under 15 years old (P value = 0.003, AOR = 3.788, 95% CI: 1.593–9.003)Conclusion: Considering that household contacts consist of a recognizable group of individuals under 15 years old with a high risk of disease, as they live in close proximity to a source of infection, it is essential to focus on education, routine screening, and the application of chemoprophylactic protocols towards leprosy prevention among household contacts, especially blood relatives.