Objective: To identify risk factors for lower quality of life (QOL) in non-metastatic breast cancer patients.Methods: Our study included 120 patients from the University Hospital Centers of Tours and Poitiers. This cross-sectional study was conducted 7 months after patients’ breast cancer diagnosis and assessed QOL (Quality of Life Questionnaire-Core 30 = QLQ-C30), socio-demographic characteristics, coping strategies (Brief-Cope), physiological and biological variables (e.g., initial tumor severity, types of treatment received), the existence of major depressive disorder (Mini International Neuropsychiatric Interview) and pain severity (QDSA). We assessed personality disorders 3 months after diagnosis (VKP questionnaire). We used multiple linear regression models to determine which factors were associated with physical, emotional and global QOL. Results: Lower physical QOL was associated with major depressive disorder, younger age, a more severe initial tumor stage and the use of the behavioral disengagement coping. Lower emotional QOL was associated with major depressive disorder, the existence of a personality disorder, a more severe pain level, higher use of self-blame and lower use of acceptance coping strategies. Lower global QOL was associated with major depressive disorder, the existence of a personality disorder, a more severe pain level, higher use of self-blame and lower use of positive reframing coping strategies and an absence of hormone therapy.Conclusions: Lower QOL scores were more strongly associated to variables related to the individual’s premorbid psychological characteristics and the manner in which this individual copes with the cancer (e.g., depression, personality and coping) than to cancer-related variables (e.g., treatment types, cancer severity).