High-flow nasal cannula oxygen therapy (HFNC) is increasingly used to treat bronchiolitis. However, HFNC has not reduced time on supplemental oxygen, length of stay (LOS), or ICU admission. Our objective was to reduce HFNC use in children admitted for bronchiolitis from 41% to 20% over 2 years. Using quality improvement methods, our multidisciplinary team formulated key drivers, including standardization of HFNC use, effective communication, knowledgeable staff, engaged providers and families, data transparency, and high-value care focus. Interventions included: (1) standardized HFNC initiation criteria, (2) staff education, (3) real-time feedback to providers, (4) a script for providers to use with families about expectations during admission, (5) team huddle for patients admitted on HFNC to discuss necessity, and (6) distribution of a bronchiolitis toolkit. We used statistical process control charts to track the percentage of children with bronchiolitis who received HFNC. Data were compared with a comparison institution not actively involved in quality improvement work around HFNC use to ensure improvements were not secondary to the COVID-19 pandemic alone. Over 10 months of interventions, we saw a decrease in HFNC use for patients admitted with bronchiolitis from 41% to 22%, which was sustained for >12 months. There was no change in HFNC use at the comparison institution. The overall mean LOS for children with bronchiolitis decreased from 60 to 45 hours. We successfully reduced HFNC use in children with bronchiolitis, improving delivery of high-value and evidence-based care. This reduction was associated with a 25% decrease in LOS.