In long-term care facilities (LTCF), registered nurses (RNs) perform both clinical and supervisory roles as part of a team aiming to provide high-quality care to residents. The residents have several co-morbidities and complex care needs. Unfortunately, new RNs receive minimal preparation in gerontology and supervisory experience during their program, leading to low retention rates and affecting resident outcomes. This qualitative study explored factors that influence supervisory performance of new RNs in LTCF from the perspective of 24 participants from Ontario, Canada. Data were collected through individual interviews, followed by a directed content analysis. Three levels of influences were identified: personal influences, organizational influences, and external influences. Each level presented with sub-elements, further describing the factors that impact the supervisory performance of the new RN. To retain new RNs in LTC, organizations must provide additional gerontological education and mentoring for new RNs to flourish in their supervisory roles.