Background/Purpose: To examine the influence of parenteral nutrition (PN) on clinical outcomes and cost in children with complicated appendicitis. Methods: Retrospective study of 1,073 children with complicated appendicitis from 29 hospitals participating in the NSQIP-Pediatric Appendectomy Pilot Collaborative (1/2013-6/2015). Mixed-effects regression was used to compare 30-day postoperative outcomes between high and low PN-utilizing hospitals after propensity matching on demographic characteristics, BMI and postoperative LOS as a surrogate for disease severity. Results: Overall PN utilization was 13.6%, ranging from 0-10.3% at low utilization hospitals (n = 452) and 10.3-32.4% at high utilization hospitals (n = 621). Outcomes were similar between low and high utilization hospitals for rates of overall complications (12.3% vs. 10.5%, OR: 0.80 [0.46,1.37], p = 0.41), SSIs (11.3% vs. 8.8%, OR: 0.72 [0.40,1.32], p = 0.29) and revisits (14.7% vs. 15.9%, OR: 1.10 [0.75,1.61], p = 0.63). Adjusted mean 30-day cumulative hospital cost was 22.9% higher for patients receiving PN ($25,164 vs. $20,478, p < 0.01) after controlling for postoperative LOS. Conclusion: Following adjustment for patient characteristics and postoperative length of stay, higher rates of PN utilization in children with complicated appendicitis were associated with higher cost but not with lower rates of overall complications, surgical site infections or revisits. Level of Evidence Level III: Treatment study - Retrospective comparative study (c) 2021 Elsevier Inc. All rights reserved.