Background Postoperative agitation is characterized by increased recovery time, irritability, and disorientation. This study hypothesized that adding nalbuphine to caudal bupivacaine could improve postoperative emergence agitation (EA). Methods Eighty children (2-12 years and ASA I-II) undergoing sub-umbilical abdominal surgeries were randomly allocated into two equal groups. Group-B received caudal bupivacaine 0.125 of 1 ml/kg plus 2 ml normal saline, whereas Group-N received caudal bupivacaine 0.125 of 1 ml/kg plus 0.2 mg/kg nalbuphine diluted in 2ml normal saline. We evaluated postoperative EA according to the pediatric anesthesia emergence delirium scale (PAED) on admission to the PACU and every 30 minutes for two hours postoperatively. Postoperative pain, sedation, rescue analgesia complications, and parents’ satisfaction were also recorded. Results No statistically significant difference between both groups regarding the postoperative PAED scale at different times (p > 0.05), but inside each group, there was a significant decrease PAED scale at different times of assessment (p < 0.001) as compared to baseline data. Group-N had significantly better results concerning postoperative sedation and analgesia. No significant differences between study groups as regardingthe hemodynamic parameters. Group-N had a significantly prolonged time to 1st analgesic request, lower total rescue analgesia consumption, and more parents’ satisfaction scores. No serious adverse effects were recorded during the study. Conclusion Adding nalbuphine to bupivacaine during pediatric caudal block had no significantly different effects on postoperative EA (PAED score). Both drugs decreased the incidence of EA with less severity in the nalbuphine group. Nalbuphine also decreases postoperative pain with more sedation.