Gary beat off competition from the likes of David Beckham, Simon Cowell and Peter Andre in the icelolly.com contest, which was voted for by the public.
Gary, 44, who has three children - Daniel, Emily and Daisy - with wife Dawn, claimed the coveted award for the second time, having already won in 2012.
The singer said: "I'm absolutely made-up to have been voted icelolly.com Celebrity Dad of the Year 2015 and I'd like to thank everyone who voted for me.
"I've got to be honest, I'm always a bit dubious about awards - The BRITs, Oscars…but Celebrity Dad of the Year get it right, and they've got it right twice now. I think 2012 and 2015 in particular the audience has spoken and they know what they want!"
Other celebrities who made the shortlist include Gary's former bandmate Robbie Williams, Tom Fletcher, Rio Ferdinand, Marvin Humes and Prince William.
While Gary has scooped the best dad gong, in March, TOWIE star Billie Faiers said she was "honoured" to be crowned Celebrity Mum of the Year.
The boutique owner and mum-of-one beat the likes of Katie Price, Frankie Bridge and Holly Willoughby.
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