Abstract : Breast Cancer is a malignancy in the breast that often occurs in women and is the second leading cause of death after lung cancer. Mastectomy is a treatment that is performed to treat breast cancer. Several factors affect a person doing a mastectomy, including the motivation and attitude of the client with breast cancer. The purpose of this study was to be able to explain the effect of attitudes and motivation on mastectomy in breast cancer clients in Indonesia. The research design used was research with correlation analytic design and using a cross-sectional approach. The sample in this study was breast cancer patients at Indonesia. The sampling technique used in this study was Consecutive sampling. The results of the analysis were obtained from 83 respondents. The majority of respondents did mastectomy (51.8%), had negative attitudes (57.8%), and had the weak motivation (57.8%). There was a relationship between attitudes toward mastectomy with statistical test results obtained p value =0.030, and there is a relationship between motivation and mastectomy with the results of the statistical test obtained p = 0.002. It is expected that nurses as providers of nursing care can continue to motivate clients with breast cancer to always try to do the right management.