Heigl (Heigl image available here), a star of US television series "Grey's Anatomy" whose film credits include "Knocked Up" and "27 Dresses," topped AskMen's eighth annual list of "The 99 Most Desirable Women."
More than five million votes were cast at the website during a six-week poll asking which women in the worlds of fashion, music, or entertainment most embody the qualities of an ideal girlfriend or wife.
Victoria's Secret lingerie model Alessandra Ambrosio was the second top choice while actress Kate Beckinsale was voted into third place.
"The poll continues to bring a smile to my face each year," said actress and television entertainment correspondent Maria Menounos, who was the 11th-highest vote-getter.
AskMen says it urged voters to look beyond beauty to qualities such as humor, intelligence, ambition and charisma desired in a companion.
"We love the diversity of the list," said AskMen editor-in-chief James Bassil.
"There is at least one woman on the list that each of our eight million readers would find as their perfect companion."
The top 10 partner picks at AskMen include actresses Eva Mendes, Jessica Alba, Scarlett Johansson and Jessica Biel as well as singer Rihanna and supermodels Marisa Miller and Adriana Lima.
"I guess it's better than the alternate lists, 'the not-so-hot of the year!' quipped "Desperate Housewives" television show star Eva Longoria Parker, who ranked 29th in the poll.
Eighty-eighth place went to self-described video game lover Jessica Chobot, who became an Internet sensation after a modeling photo of her licking a Sony PSP portable gaming device was posted online.
Her celebrity won her a spot as a host at game and entertainment news website IGN.com.
AskMen is a unit of Fox Interactive Media and bills itself as the world's leading men's lifestyle website with more than seven million readers monthly.