The Olympic gold medallist and her impressive abs came top of a survey conducted by Lifestyle 247 Bootcamps.
Rosie Huntington-Whiteley, Rihanna and 49-year-old supermodel Elle Macpherson also finished high.
The survey revealed that 81% of male respondents would rather date an athletic woman than one with a skinny frame, while 35% of women said they felt "repulsed" by pictures of super-skinny celebrities.
Speaking in August, Ennis declared that winning the heptathlon at London 2012 had surpassed all of her dreams.
"It's one thing winning an Olympic medal, but it's another doing it on your home country," she said.
"I was completely taken aback. It was really overwhelming. There was so much positivity in the stadium."
The Top 10 most desirable celebrity bodies in full:
1. Jessica Ennis
2. Kelly Brook
3. Kim Kardashian
4. Rosie Huntington-Whiteley
6. Elle Macpherson
7. Halle Berry
8. Gisele Bundchen
9. Miranda Kerr
10. Frankie Sandford
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