The Wanted singer was impressed by the 60-year-old showbiz matriarch's cheeky questions when the band appeared on US chat show 'The View' and thinks 'The X Factor' UK judge is very attractive for an older woman.
He explained to Top of the Pops magazine: ''Sharon Osbourne was one of the hosts and she asked us which of the ladies we would go for, so I said her! She's a right flirt, is Sharon!''
However, the 24-year-old hunk - who has been loved-up with Kelsey Hardwick for the last three years - was less smooth under pressure during a recent trip to Paris, France, where he embarrassed himself in front of a crowd of adoring female fans.
Tom explained: ''We had a great time in Paris, the city of luuurve! We came out of our hotel room and on to the balcony to watch some fans singing 'Walks Like Rihanna' to us, which was nice.
''Everything was going well until I walked straight into a glass door in the hotel lobby and banged my head. It hurt. A lot.''
The BBC drama starring Aidan Turner returns to BBC One on September 4th.