Background : Postoperative pain after cardiac surgery can persist for extended periods, with up to 43% of patients experiencing pain three months post-surgery, and is associated with inadequate management and intense acute postoperative pain. Peripheral sensitization due to tissue injury and central sensitization within the central nervous system contributes to heightened pain sensitivity post-surgery. While opioids are effective, concerns over their adverse effects and potential for misuse prompt a shift towards multimodal analgesia, including regional anesthesia. Despite its advantages, there has been no comprehensive review comparing regional anesthesia and opioids in cardiac surgery. This study aims to systematically review randomized controlled trials to compare the effectiveness of these pain management strategies. context and purpose of the study.Methods: The literature search was performed across four databases. This study focuses on the postoperative pain scale. Regional block intervention relieves pain in cardiac surgery patients by administering local anesthetics near nerves, which minimizes reliance on systemic opioids and their associated side effects. This approach enhances patient comfort, accelerates recovery, and reduces the risk of opioid dependence. Quality was assessed using the Cochrane Risk of Bias Tool 2. A total of ten articles were included in this systematic review.Result : The analysis of pain scale data from eight studies revealed significant reductions in postoperative pain with regional block interventions compared to controls. Opioid consumption was notably reduced, indicating a decreased reliance on opioids. The length of time to extubation varied, with the intervention group showing a shorter duration compared to the controls. Adverse effects, including diaphoresis and nausea, were reported, but further research is needed to investigate these effects thoroughly.Conclusion: Regional anesthesia has proven effective in reducing postoperative pain and minimizing both the dose and duration of opioid use.