Treating pain during vaccination should be a part of pediatric primary health care around the world, as untreated pain in children has short and long-term consequences. Few studies of pharmacologic and non-pharmacologic methods of pain relief during immunization have been conducted in low-and-middle-income countries. Finding a cheap and effective pain intervention would improve primary health care. The current study aimed to evaluate the effectiveness of oral sucrose as a method of pain management during immunization among infants through six months of age. A randomized controlled experimental design was used. The study sample included 80 infants distributed into sucrose and control groups. Data were collected in an Egyptian primary health center. Outcome measures, including pain, as measured by the FLACC pain scale, crying time, and heart rate, were measured at three time points (before, during, and after injection). There were statistically significant differences during and after immunization (p < .001) reflecting lower: scores of pain, crying duration, and rising in heart rate for the sucrose group compared to the control group. The study supports the effectiveness of oral sucrose in managing infants' immunization pain and recommends for providing clinical setting with safe resources and education for proper administration of oral sucrose in pain management.