The honor was announced on the late night US TV show hosted by Jimmy Kimmel on ABC and in the magazine itself.
With his face at first masked and his voice digitally modified, Hemsworth, 31, speaking from Australia, toyed with playful yes-or-no questions from the American TV audience.
Kimmel's instructions and teasers to his crowd: "If you guess correctly, the sexiest man alive will make love to you, so this is big. I will give you three clues. He is sexy, he is a man, he is alive."
Is he in a band? No. Over age 35? Wrong, again.
"Are you hairy?" a bearded, balding man in the audience asked, smiling.