Abstract: A quasi-experimental, post-test only control group design study was undertaken to evaluate the effectiveness of breastfeeding on relief of pain during DPT immunization with that of non-breastfeeding during DPT immunization for the infant of the age group between 6 -17 weeks at the immunization clinic in selected PHC of Manipur .The main objective is to find out the effectiveness of breastfeeding on relief of pain during DPT immunization. The theoretical framework adopted for the study was based on gate control theory. Experts established the content validity of the tools.