Background: In Iran, there are high rates of breast cancer. It is among the five most common cancers, the first among cancers diagnosed, and is the leading cause of cancer deaths among Iranian women. Objectives: The purpose of this qualitative study was to explore perception of breast cancer screening among Iranian women who have never had a mammograph. Materials and Methods: The current study was part of a qualitative research conducted by means of content analysis method and purposive sampling of 16 women over the age of 30 years who had not undergone mammography using individual semi-structured interviews. Interviews were recorded and transcribed verbatim. The data were under continuous consideration and comparative analysis in order to achieve data saturation. Results: After codification of data, three concept categories were achieved including: i) low awareness, ii) worries, and iii) lack of motivation. Conclusions: Although there is a tendency among Iranian women to participate in breast cancer screening, there is a powerful cultural belief that breasts are sexual organs that should not be discussed publicly. Due to the incidence of breast cancer in Iranian women, it is critical that breast awareness education be performed by health care experts to explore the concepts of breast cancer and breast cancer screening.