Introduction: Health is a significant value in every person’s life. The effectiveness in obeying recommendations regarding health behaviors depends on one’s belief concerning their health locus of control. Aim: To present the relations between preferred health behaviors and health locus of control in women after mastectomy, as a determinant of returning to optimal health. Material and methods: The study was conducted among 98 patients of the Clinical Department of Breast Cancer and Reconstructive Surgery in Oncology Centre in Bydgoszcz. Health behaviors were assessed using the Health Behaviour Inventory by Juczyński and health locus of control was determined using an MHLC questionnaire version B, in the adaptation of Juczyński. Results: The examined women present an average level of health behaviors. The higher their education, the higher level of health behaviors. Among all the dimensions of health locus of control, the highest scores were gained in the dimension of chance and the lowest in the dimension of internal control. The greatest number of high scores was obtained in the dimension of chance and the lowest - in the dimension of influence of others. Conclusions: The obtained results allow for a better recognition of the needs of women with breast cancer. They may serve as educational materials for medical personnel to help to introduce certain modifications in their patients’ lifestyles.