Background: This study examined what factors affected a complete examination of infant health checkup. Methods: We used Korean national health insurance claim data of 2,936,650 infants, taking examination in 2012. These claim data included enrollment status of householders and records of infant health checkup from 2008 to 2013. Results: Our results shows that for infant characteristics, the likelihood of complete examination of infant health checkup is significantly lower in female, older aged, and handicapped ones. For householder characteristics, the likelihood of complete examination of infant health checkup is also significantly lower in female, older group and self-employed ones. For household characteristics, the likelihood of complete examination is also significantly lower in single-parent families, multi-cultural families, parent with unexperienced health checkup and lower monthly premiums. Conclusion: It is necessary to support an additional use-guide and follow-up management services to improve incomplete examination of infant health checkup.