Background: Children are always dependent, can’t say about their needs or pain always. This cannot be neglected at any cost as excess pain can damage nerve cells & many more. But Consideration about pain during procedures for toddlers is a less talked topic as far as the actual application is concerned in Odisha. Thus the researcher felt the need of doing a study on this Diversional therapy as bubble popping can easily distract and hold the mind of the children for a while & is cheap. Aim & Objective: To evaluate the effect of bubble popping therapy on behavioral response to pain perception among toddlers during parenteral vaccination. Material & methods: Thus a quasi-experimental study was conducted among 60 samples (13-24 months), where both experimental & control groups contain 30 samples each. Purposive sampling techniques were adopted. Experimental group were given diversion during parenteral vaccination. FLACC behavioral pain assessment scale was used to measure the behavioral response to the level of pain. Result: The mean score of the control group was 7.68 & that of the experimental group is 4.48 with a mean difference 3.20. The obtained ‘t’ value is 8.42 at ‘p’ < 0.05 (2.01). Henceforth we rejected the null hypothesis and accepted the research hypothesis. Conclusion: Thus bubble popping is effective in reducing pain among toddlers during vaccination