Objective: to establish a relationship between osteoporosis and the development of pain syndrome in patients with breast cancer (BC) during performed treatment and to enhance the efficiency of the diagnosis and prevention of osteoporosis. Subjects and methods. The investigation enrolled 77 women, including 47 BC patients aged 30 to 50 years (a study group) and 30 women of the same age (a control group). Osteodensitometry was performed and biochemical markers for osteoporosis were determined in all the patients. The degree of pain syndrome in BC patients was estimated using the McGill pain questionnaire and criteria for the pain syndrome classification developed by the authors. Patients with breast cancer were examined before and 6 months after special treatment. Results. Pain syndrome appeared and became severe in 39 (76.6%) out of the 47 childbearing-aged patients with BC after artificial menopause 6 months after special treatment for the underlying disease. Artificial menopause was associated with chemotherapy and termination of ovarian function. Hormone therapy with tamoxifen was used in 30 BC patients, 12 of them were switched to second-line hormone therapy because of the side effect of antiestrogens. At the same time menopause is a major condition for using aromatase inhibitors. An examination of the entire group of patients revealed osteopenia and osteoporosis in 63.8%. Conclusion. The incidence of osteoporosis and pain syndrome in patients with breast cancer is directly linked with the performed specific treatment, during which it is necessary to concurrently use preventive therapy for osteoporosis and combination treatment for BC.