Abstract: This study on exclusive breast-feeding and child immunization on child mortality provides opportunities to continuously improve child health and reduce mortality. The ex-post facto design was employed while two research questions and two hypotheses gave direction to the study. The population was all children below their fifth birthday in 300 hundred households. The multi-stage sampling technique was combined with the ballot and systematic method to select 20 households in the state. The research instrument was standardized multi topic household survey instrument designed by Grosh and Glewwe (2002). It was reliable at 0.90. It was found that exclusive breast feeding and child immunization have no significant relationship on child mortality. This is so because exclusive breast-feeding and child immunization is not significantly practiced in Delta State, Nigeria. The practical implication of this study was the call for inhabitant of Delta State, Nigeria to pay more serious attention to child immunization and exclusive breast-feeding through organized Health Education Programme in Schools, Churches and Community Health Programme and through the media. This study has revealed the low child immunization coverage and low participation of reproductive women in exclusive breast-feeding in Delta State, Nigeria. Hence child immunization and exclusive breast-feeding cannot be a determinant of child mortality at the present level of practice in Delta State, Nigeria.