The Baby hitmaker has been in the music industry since the age of 13, and he spent his teenage years as a hugely famous child star. He has been in a downward spiral recently, suffering numerous legal troubles, including a Dui arrest and a vandalism conviction, as well as becoming notorious for his bad behaviour.
O'Connor has now become the latest celebrity to wade into the debate over how the clean-cut pop star became a bona fide bad boy, insisting Bieber's status as a teenage pin-up contributed to his downfall.
She tells British radio station Magic Fm it is not just young female singers who fall prey to the dangerous side of the industry.
O'Connor says, "I think that people focus an awful lot on the female aspect to this, but it is also the males. The very young male artists who are practically children or look like children are also being sexualised. Justin Bieber is a great example. When he came along he was only 16 years of age (sic). Obviously he was extraordinarily talented, so I'm not trying to negate that, but he was very much being sold on his sexuality."
The singer fears Bieber and other young male celebrities are doomed to follow in the footsteps of Britney Spears, who shot to fame as a child star and became an international sensation before suffering a highly-public meltdown in her 20s.
She adds, "Britney Spears, of course was quite inappropriately young to be sold in that way, dressed up in a school uniform (in her ...Baby One More Time video), but I think that really people forget that the guys are going through it as well."
O'Connor has suffered her own troubles in recent years as she has battled mental illness and has previously insisted life in the music industry exacerbated her problems.
The full interview with O'Connor airs on Britain's Magic Fm on Sunday (10Aug14).