The study undertaken the assessment of awareness and specific knowledge, perceived susceptibility, perceived seriousness of breast cancer and perceived benefits of screening for early detection and treatment of women in a differ community. The study also measured screening behavior among the participants. Therefore, the aim of this study was to assess and compare the knowledge and perception of Saudi Arabia and Sudanese people towards breast cancer prevention and early detection. In this comparative, cross sectional study, data about breast cancer were obtained from 1000 participants: 500 Saudi volunteers living in the city of Hail, Saudi Arabia and 500 Sudanese volunteers living in Khartoum city. The level of individual's knowledge about breast cancer was assessed, the majority of the study subjects were found with moderate knowledge followed by good, Excellent, poor and no knowledge representing 432(43.3%), 332(33.3%), 116(11.6%), 107(10.7%) and 10(1%), respectively. For Saudi, most of them were found with moderate knowledge followed by excellent, good, none and poor knowledge constituting 66(27.2%), 112(46.2%), 32(13.2%), 29(11.9%) and 3(1.2%), respectively. For Sudanese, most of them were found with moderate knowledge followed by Excellent, good, none and poor knowledge constituting 266(35.2%), 320(42.3%), 84(11.1%), 78(10.3%) and 7(0.9%), respectively. The overall knowledge of the studied population about breast cancer prevention and early detection was relatively low. More community based health education efforts are needed to reduce the burden of breast cancer in both nations.