The 48-year-old singer, who has long battled an addiction to drugs, is on parole after serving several months in jail this year for imprisoning a male escort in 2007.
The BBC said Boy George's lawyers petitioned the Probation Service to allow him to appear on "Big Brother."
But Justice David Bean ruled Wednesday the agency has the right to keep the singer off the airwaves. The judge also noted that having his freedom restricted is part of Boy George's punishment for the crime he committed.
"I consider that right-thinking members of the public would take the view that an offender serving the non-custodial part of a sentence of imprisonment should not be allowed to take part in a high-profile, controversial television production, promoting his status as a celebrity and with considerable financial gain," the BBC quoted Bean as saying.