Background: The majority of children with bone sarcomas experience pain. Opioids remain the mainstay treatment of cancer-related pain in children. The patterns of outpatient opioid prescription after surgery for primary bone sarcomas remains unknown. The purpose of this study is to evaluate the patterns of outpatient opioid prescription in patients with bone sarcomas after resection of the primary tumor, and to assess for factors that may lead to increased opioid dosing in these patients. Methods: A retrospective chart review of 28 patients with bone sarcomas undergoing primary tumor resection was performed. Demographic, medical, surgical, and pharmacological data was collected from all patients. The total morphine milligram equivalents (MMEs) prescribed after patient discharge were compared at 30-day intervals. The MMEs were then stratified by tumor location, presence of metastasis at time of surgery, and preoperative opioid use. Independent predictors of increased 30-day and total 120-day opioid utilization were evaluated. Results: Patients with preoperative opioid use were prescribed significantly more opioids in every 30-day postoperative interval and for the 120-day total. When stratified by tumor location, patients with primary tumors in the pelvis had significantly greater postoperative opioid utilization when compared with patients with tumors located in the lower and upper extremities during postoperative days 61 to 90 (5970 vs. 1060.4 and 0 MMEs, respectively, P=0.048) and during postoperative days 91 to 120 (6450 vs. 829.6 and 0 MMEs, respectively, P=0.015). Older age, diagnosis of osteosarcoma, increased length of stay postoperatively and presence of metastases were associated with a higher 30-day postoperative opioid utilization. Conclusion: Multiple factors were associated with increased opioid use including preoperative opioid use, longer postoperative stay in the hospital, metastatic disease, and primary sarcomas in the pelvis. The patient’s sex, body mass index, race, type of insurance, type of surgery performed, reoperation during the same admission and use of nonopioid adjuvants had no effect on opioid use. The results of this study can be used to stratify the average opioid requirement of pediatric patients undergoing primary bone sarcoma resection. Level of Evidence: Level IV.