The 52-year-old musician - who has previously battled heroin and cocaine addiction and served time in jail - believes Justin, 19, may have already been ''involved'' with drugs and thinks the 'Beauty and a Beat' hitmaker should be ''taken more care of'' before he becomes too caught up in the culture.
George said: ''I think drugs are involved with Justin Bieber.
''I look at Justin and think, you're gonna learn that all of this is such a waste of time.
''It's so difficult to do all your learning in public though, I'm surprised young celebrities aren't taken more care of.
''But if you're controlling someone, you're probably gonna drive them towards more disruptive behaviour.
''Being such a major f**k-up I know how wilful I was, I know how hard it is for anyone to stop you, particularly when you're famous and people are employed by you.
''If someone stands up to you as a celebrity, what you gonna do, fire them? Probably.''
While he believes there is still hope for Justin, the singer-turned-DJ hit out at Rihanna for posting several pictures of herself smoking cannabis on social networking sites, insisting she has a ''real problem''.
The former Culture Club star explained: ''When an artist is doing something like that, that's when you know they've got a real problem. When you have no boundaries with yourself and you're prepared to break the law on Twitter, that's kinda scary. What you do in your own time and what you do that influences fans are very different. Of course if you're a f**k-up, people will see you're a f**k-up, but I don't think you should celebrate it.''
George, who is openly gay, clashed with One Direction singer Liam Payne earlier this year, describing him as a ''twit'' who deserves to be punched, and joked he would be ''disappointed'' if the boy band didn't turn out to be bisexual.
He added to the Daily Star newspaper: ''The odds are one of One Direction must be gay. I think everyone is a bit bisexual deep down, so the odds are they are probably all bisexual. They're rock stars so it's what you'd expect, isn't it? I'd be disappointed if they weren't. Tattoos don't make you butch. Look at me.''
There are currently five separate teams working on 'Game of Thrones' projects at HBO.
She's a big fan of the band and this week she got to perform with them.