The former X Factor champ, who was dropped after only the one album with Simon Cowell's Syco record label earlier this year, was approached by show bosses.
It had been reported this week that James was in talks with show bosses to pause the music career and enter thew new CBB house next month.
But he tweeted today to deny he'd be taking part but did confirm he had been offered a deal to become a housemate.
James took to Twitter to say: "Rule me out of that I am not doing CBB. I'm a big fan but I have turned down an offer from them."
Other celebs who are said to have turned down the new series include Corrie actor Bill Roache, Benefits Street star White Dee and Boyzone's Ronan Keating.
As for who could actually be on Celebrity Big Brother this yea, some of the names more positively linked to the show include Gladiator David McIntosh aka Tornado, Hollywood actor Gary Busey, writer Julie Burchill, and former TOWIE star Lauren Goodger.
Also linked to the new series are Misfits actress Lauren Socha, BGT's Lettice Rowbotham, dominatrix Natalie Rowe, Made In Chelsea's Stephanie Pratt and most recently soap actor Michael Le Vell.
CBB will air on Channel 5 from August.
Browse pictures of some of the rumoured Celebrity Big Brother housemates below...