Introduction: this study was performed to investigate of role of Self-differentiation and Self-conscious (shame and guilt) in predicting the quality of life of women with breast cancer in Tehran.

Methods: This study was a cross-sectional study; the sample consisted of 200 women with cancer who refer to Imam Hossein Hospital. To gather the data, the Self-differentiation Scale (DSI-SF-20), the Self-conscious (GAPS-16), and the Quality of Life scale (SF-12) were used. Data was analyzed through analysis of regression by SPSS₂₀ software.

Results: Results showed that there was a significant positive correlation among Self-differentiation with Physical and mental dimensions of Quality of Life, and a significant negative correlation among Self-conscious (shame and guilt) with Physical and mental dimensions of Quality of Life. Also, regression analysis indicated that Self-differentiation and Self-conscious significantly predicted 28% of the variance of Physical dimension and 41% of the variance of mental dimension of Quality of Life.

Conclusion: The results of this study Suitable for Psychologists and related professionals, to help breast cancer patients, in order to increase the ability of self-differentiation and decrease the emotions of shame and guilt, that it can improve the quality of life of these patients.