Positioning the babies while administering intramuscular vaccinations in a comfortable position. This study is aimed to assess the pain in supine versus sitting position during intramuscular injection among infants from selected immunization clinics. Method: A descriptive observational study group methodology was employed in this investigation. By using the purposive sampling strategy, 60 samples were chosen. The NIPS pain scale was utilised in this investigation to assess the severity of the pain. Results: In the supine position, 66.7% of the babies experienced mild to moderate pain during vaccination, compared to 33.3% of those who experienced severe pain. In the sitting posture, 40% of the babies experienced mild to severe discomfort, and 60% of them experienced little to no pain. Infants in the supine position had an average mean pain score of 4.3, whereas those in the sitting posture had an average mean pain score of 2.4. This test has a T-value of 21.3. The null hypothesis is disproved due to the modest corresponding p-value (less than 0.05). Infants substantially experienced more pain on an average when lying flat as opposed to when they were sitting up. Thus, it is clear that newborns experience substantially less discomfort while receiving intramuscular injections when seated than in sleeping position.