Purpose To compare compliance with the French national guidelines before and after the implementation (in 2018) of a new protocol on acute fracture pain management in the pediatric emergency department of a French university medical center. Methods We conducted a retrospective, before-after study in patients aged below 16 years presenting at the pediatric emergency department with a fracture. We compared pain management before (in 2017) and after (in 2019 and 2020) implementation of the new procedure. The primary endpoint was appropriate pain management, defined as (i) an appropriate initial assessment of pain, (ii) appropriate treatment with analgesic drugs (acetaminophen for mild pain, acetaminophen and ibuprofen for moderate pain, ibuprofen and morphine for severe pain) and (iii) reassessment of the pain intensity. Results 572 patients were included (mean age: 6.5 years; male: 60%). 190 in 2017 and 382 in 2019–2020. Pain management was appropriate for 40% of the patients in 2017 and 52% in 2019–2020 (p = 0.004). Pain was rated for 98% of patients in 2017 vs. 100% in 2019–2020 (p = 0.04). The frequency of appropriate treatment for mild pain and moderate pain increased significantly from 52 to 76% and from 0 to 44%, respectively. The administration of ibuprofen increased by 26% points (from 3 to 20 patients treated) and the administration of morphine increased by 29% points (from 1 to 17 patients treated). Pain reassessment rose significantly from 21 to 43%. Levels of compliance with the guidelines were similar in 2019 and 2020. Analgesia was significantly more effective in 2019–2020 than in 2017 (in 20% vs. 14% of the patients, respectively; p = 0.005). Conclusion After the implementation of a new protocol for the management of acute fracture pain, we observed an increase in compliance with the guidelines. Although the use of ibuprofen and morphine rose significantly as did the frequency of pain reassessment, further improvements are required.