British funnyman Gervais, 49, sparked controversy after he poked fun at several stars while he hosted this year's Golden Globes awards show.
But Kelly wrote in her column for British Closer magazine that she thought Ricky was not 'nasty at all'.
The 26-year-old wrote: 'To all the people criticising Ricky Gervais – get a sense of humour! He was a great host at the Golden Globes and I thought his jokes were brilliant. He wasn’t mean or nasty at all, it’s just comedy. Good on you, Ricky!'
Osbourne, who has just been named as the new face of Madonna's Material Girl line, also discussed Piers Morgan's new CNN show Piers Morgan Tonight.
She added: 'He's a family friend and I remember him saying months ago that he'd love to interview Oprah, so she was a fab guest to have on the first show. As I know from when I appeared on his Life Stories series last year, he can make anyone open up like they are talking to their best friend and, like me, Oprah cried (when she was talking about the influence Martin Luther King had on her life).
'Piers had a hard act to follow replacing Larry King, but the ratings were great and I think he's a worthy successor!'