BACKGROUND: Breast cancer is a major public health concern in both developing and developed countries. The mortality rate of breast cancer is high in India due to late detection, and lack of knowledge about the screening mammography. The objective of this study was to develop and establish the psychometric properties of the tool.METHOD: A qualitative method was used to carry out the development and validation of a tool to assess the knowledge, attitude, and perception of women towards screening mammography using a cross-sectional study design. Data analyzed using the SPSS 16 were descriptive, and Cronbach's alpha coefficient was used to standardize the tool.RESULTS: The pilot test, content validity, and internal consistency reliability of the final 25 items were found to be highly adequate. Intra- class correlations of this questionnaire were considered acceptable. Cronbach’s alpha score was 0.825.CONCLUSION: A valid scale has been developed to evaluate the knowledge, attitude, and perception of women toward screening mammography. The scale is adequately responsive to test the knowledge and possesses strong internal consistency. Lack of knowledge among the general population about the screening mammography. It is recommended to conduct an educational program to enhance knowledge about screening mammography. The questionnaires can be used for evaluating the knowledge, attitude, and perception of women toward screening mammography. Broadening the concept for further questionnaires tool development of knowledge, attitude, and perception of women towards screening mammography in other geographical areas.KEYWORDS:Reliability, Screening Mammography, Validity