This study assessed the knowledge of breast cancer and early detection measures of reverend sisters in Anambra State. Eight objectives and eight research questions were raised to guide the study. Cross-sectional descriptive survey design was used. A sample size of 324 respondents was drawn from an estimated population of 794 sisters of the various congregations living in communities located in Anambra State through stratified, proportionate and convenient sampling techniques. Data were collected by administration of a 17-item self-developed questionnaire through personal contacts by the researcher and 3 research assistants. Data were analysed descriptively using frequencies and percentages. Unpaired t-test was used to compare the responses of the two groups of respondents. There was significant difference in the knowledge of breast cancer preventive measures among the respondents. Only 61 (18.8%) of the sisters described breast cancer as uncontrolled multiplication of breast tissue. As many as 52 (16.0%) of the respondents had no idea of what breast cancer means. Painless lump was identified by 141 (43.5%) respondents as the early warning sign of breast cancer. There was no significant difference in the awareness of early warning signs/symptoms of breast cancer among the two groups (0.7438>p0.05) and what the two groups knew as breast examination (0.8608>p0.05). Most popular breast cancer early detection practices identified was breast self examination. More sisters in the active group seem to be aware of this than the contemplatives. A good number of them had never done breast self examination 50 (15.4%) and clinical breast examination 158 (48.8%). As many as 148 (45.7%) respondents were not aware of where to obtain the services, and 73 (22.5%) avoided the detection measures because of fear of lumps. Not being aware of where to obtain the services was a factor to reckon with, while at the same time, the sisters preferred to live in ignorance for fear of a lump being detected. Congregations should establish policy guidelines aimed at promoting adequate and urgent dissemination of all relevant information about breast cancer; and, integrate breast cancer screening procedures into their curriculum. There should be free access to screening services in the government health institutions.