Background: Worldwide, breast cancer is a significant health issue for women. The removal of one or both breasts in women can frequently result in physical complications, emotional struggles like depression and stress, and issues in marital relationships. Aim: The study aimed to evaluate the effect of educational-supportive program about therapeutic exercises on women's physical, psychological and marital status undergoing mastectomy. Design: Quasi-experimental research (two groups, ″control - study″) design was utilized to fulfill the aim of this research. Setting: Early breast cancer detection unit affiliated to Benha Faculty of Medicine and General & Oncology Surgery Ward. Sample: A purposive sample of (86) women, the sample was divided into two groups (study group involved 43 women, while control group involved 43 women. Tools: Data collection involved six primary tools, including a structured self-administered questionnaire and the Wong-Baker Faces Pain Rating scale, Modified Fatigue Impact Scale, Shoulder ability and function questionnaire, anxiety, depression, and stress scale and ENRICH marital satisfaction scale. Results: Following the implementation of the educational support program on therapeutic exercises, the study group experienced significantly lower average scores for pain, fatigue, depression, anxiety, and stress compared to the control group. Moreover, the study group showed markedly higher average scores for shoulder function and marital satisfaction than the control group. Conclusion: Educational-supportive program about therapeutic exercises had a positive effect on women's physical, psychological and marital status of women undergoing mastectomy. Recommendation: The elements of an educational supportive program should be included as a key component of the treatment plan for women undergoing mastectomy.