Rationale: High child mortality and morbidity in developing countries are highly associated with limited access to and poor quality of health care. Utilization of health services for children plays an important role towards achieving the Millennium Development Goal in the reduction of child mortality. In Nepal, several studies reveal disparities in child health outcomes across socio-economic levels and regions of the country. Health inequalities found in the relationship between socio-demographic determinants and the utilization of child health services has not been under rigorous examination. Objectives: The primary goal of the study is to examine empirical evidence of the socio-demographic determinants of child health services utilization, such as geographical access, household income, and mother's age and education level. Methodology: Using 1996 and 2001 Nepal Demographic and Health Survey (NDHS) data, both cross-sectional and fixed-effects logit models are used to analyze the effect of the determinants health services utilization for children suffering from diarrhea and/or respiratory illness. Results: Results show inequalities in child health utilization by sex of the child, maternal education, and across household income quintiles. Overall, health use increased over time and income; however, a smaller increase is observed for the top two income quintiles. Male health service utilization improved over time across all income groups; female health use also improved with the exception of the top quintile. Conclusions: In order to improve child survival, it is important to understand the determinants of healthcare use so that appropriate policies can be developed to maximize health services utilization. This study undertakes such an analysis to understand determinants of health services utilization for children in Nepal. This study demonstrates that sex of the child, household income, mother's education, partner's employment, and distance to health provider play a role in determining health services utilization for children under-5 years in Nepal. An important health equity implication of the association is the design of health policies and programs that reach children most at risk by increasing coverage to ensure including or targeting programs towards them. The analysis highlights the usefulness of the NDHS 1996 and 2001 data as tools to conduct health services research, and in developing policies to address health inequalities and improve access to underutilized health services.