Background: Social relationship coping efficacy (SRCE) represents the ability to maintain or enhance social relationships in the context of serious illness. The purpose of the current study was to confirm the factor structure, psychometric properties, and utility of the Italian version of the SRCE scale. Methods: 181 breast cancer patients completed the SRCE-Italian (SRCE-I), the Cancer Behavior Inventory–Brief/Italian (CBI-B/I), quality of life (QOL) measures (EORTC QLQ-C30; EORTC QLQ-BR23), and the Hospital Anxiety and Depression Scale (HADS). Results: The SRCE-I was internally consistent (Cronbach alpha=.95) and factor analysis confirmed that the SRCE-I was a unidimensional construct. In terms of validity, the SRCE-I was correlated with QOL (EORTC QLQ-30, Social Functioning, r=.323, Emotional Functioning, r=.562, and Global Health/Quality of Life; r=.546) and scales of the EORTC QLQ-BR23 (e.g., Future Perspective, r=.348; Breast Symptoms, -.331). SRCE-I was also correlated negatively with the HADS (r=-.707) and positively with the CBI-B/I (r= .810), a measure of coping efficacy (all ps<.001). Mediation analyses confirmed the utility of the SRCE-I scale as a mediating mechanism in enhancing social functioning and QOL. Conclusions: The SRCE-I is a structurally sound, reliable, and valid measure that assesses the ability to maintain or enhance social support and mitigate the loss of social support. The SRCE-I can be used as a screening measure to assess low efficacy for maintaining social support or as a measure to detect the change in efficacy for enhancing social support in interventions to improve the QOL of patients.