Background and purpose: After lung cancer, breast cancer, among the prevalent cancers of the world is of the most widespread disease among women. It is the most common cause of mortality among women. This study aimed to analyze the results using breast cancer screening methods among women over 20 years old. Materials and methods: The present study is a cross-sectional-descriptive research. The sample volume is 1416 women over 20 years in Mazandaran province. One hundred forty one clusters of 10 families including 81 urban clusters and 60 rural clusters were determined at thought the province. The questionnaires were completed by the subjects through direct administration. The data were analyzed using SPSS (version 16) statistical software and descriptive and inferential statistical methods. Results: The results show that 46% of study women had self – examination record and 14.3% of them had regular and monthly self – examination, 38% of women had breast clinical examination by a physician. And 20.7%, breast clinical examination was done regularly and annually. Fourteen percent of women had mammography record, in which only 3.5% was done at a regular time interval every 3 years. Conclusion: According to the findings, women performance about the early detection of breast cancer was not satisfactory. Thus, planning and designing appropriate educational interventions within socio-cultural conditions and using health training models can lead to promoting breast cancer early detection performance among women over 20 years.