The objective of this study was to measure the impact of an intervention on pain treatment in a pediatric emergency department (ED). The application of interventions to improve pain management in DE has demonstrated diverse effects so far, most of them successful. This is a quasi-experimental before-and-after, longitudinal, prospective study.Patients were collected between January 2020 and December 2021. Principal outcome was the number of patients with moderate or severe pain who received analgesia before 30 minutes to the ED arrival. The intervention consisted of several training sessions for nursing staff, pediatricians, and trauma physicians. A total of 515 patients were enrolled, 230 during preintervention period and 285 during postintervention period. The percentage of patients receiving analgesia before 30 minutes increased from 24% to 29% and before 60 minutes increased from 31% to 42%. Time to analgesia administration decreased from 43 to 39 minutes.Only 254 patients (49%) received analgesia at some point during their stay in the ED, 137 (26.6%) before 30 minutes and 193 (37.5%) before 60 minutes. The probability of receiving analgesia was greater in patients seen by a pediatrician rather than an orthopedist (59%-37%). Metamizole was the most commonly used drug (48%), followed by ibuprofen and acetaminophen. The application strategies to enhance early pain treatment in the ED can improve analgesia administration. Training strategies aimed at healthcare personnel working in the ED can change the way they work and achieve clear benefits for the patient. The treatment of pain in the ED should begin as soon as possible, and in this objective, the involvement of the nursing staff is a priority, because they are the professional who has the best opportunity for the detection and treatment of pain from the moment of triage.