Introduction: In this study, it was aimed to determine the knowledge attitude and behavior characteristics of women between the ages of 40-69 and the factors related to early detection of breast cancer and to evaluate the related factors. Method: The cross-sectional study was conducted in two urban and semi-urban areas of Balıkesir. The population of the study consisted of 2000 women aged between 40-69 years who were enrolled in two family health centers. The sample size was calculated as at least one time mammography use rates of 40% for women over 40 years of age and a minimum of 7% deviation and 95% confidence level with a minimum of 177. The sample selection was performed by face-to-face interviews with the questionnaire form structured by the researchers. The dependent variables of the study are self breast examination and mammography at any time. The independent variables are social and demographic characteristics, general health status, utilization of health services and information about institutions, the information index and attitude index about breast cancer. In the univariate analysis of dependent and independent variables, Chi-square test and Fisher's exact test were used in categorical data. Backward elimination method was used in logistic regression model. Type 1 error value p