Aussie trio Nicole Kidman, Rose Byrne and Elle Macpherson were not too far behind with People magazine including the downunder beauties in its annual list.
Knowles, married to rapper Jay-Z, credits the January birth of daughter Blue Ivy Carter as her beauty secret.
"I feel more beautiful than I've ever felt because I've given birth," the 30-year-old singer told People.
"I have never felt so connected, never felt like I had such a purpose on this Earth."
Kidman, 44, who was People's most beautiful in 2002, is a regular on the list while 32-year-old actress Byrne and 48-year-old Macpherson joined Kate Middleton, Angelina Jolie, Charlize Theron, Adele, Sofia Vergara and Megan Fox on the list.
Last year's winner, Jennifer Lopez, also made the 2012 list.
Macpherson credited her killer curves to a clean diet, daily exercise, good genes and lots of fun.
"Do lots of sport," the supermodel told People.
"Don't worry about your silhouette, worry about how you feel."