Background:　The　study　aimed　to　describe　the　age　distribution　of　breast　cancer　diagnosis　among　Chinese　females　for　comparison　with　the　United　States　and　the　European　Union,　and　provide　evidence　for　the　screening　target　population　in　China.　Materials　and　Methods:　Median　age　was　estimated　from　hospital　databases　from　7　tertiary　hospitals　in　China.　Population-based　data　in　China,　United　States　and　European　Union　was　extracted　from　the　National　Central　Cancer　Registry,　SEER　program　and　GLOBOCAN　2008,　respectively.　Age-standardized　distribution　of　breast　cancer　at　diagnosis　in　the　3　areas　was　estimated　based　on　the　World　Standard　Population　2000.　Results:　The　median　age　of　breast　cancer　at　diagnosis　was　around　50　in　China,　nearly　10　years　earlier　than　United　States　and　European　Union.　The　diagnosis　age　in　China　did　not　vary　between　subgroups　of　calendar　year,　region　and　pathological　characteristics.　With　adjustment　for　population　structure,　median　age　of　breast　cancer　at　diagnosis　was　50　similar　to　54　in　China,　but　55　similar　to　59　in　United　States　and　European　Union.　Conclusions:　The　median　diagnosis　age　of　female　breast　cancer　is　much　earlier　in　China　than　in　the　United　States　and　the　European　Union　pointing　to　racial　differences　in　genetics　and　lifestyle.　Screening　programs　should　start　at　an　earlier　age　for　Chinese　women　and　age　disparities　between　Chinese　and　Western　women　warrant　further　studies.