The 29-year-old was due to start the Barclays Premier League clash against Blackburn but picked up the injury during a training session on Thursday.
Speaking after the 1-1 draw, QPR manager Neil Warnock revealed the injury could leave Campbell sidelined for up to two months should the bone require pinning.
In a spin: DJ Campbell will miss the next two months through injury
Club head physio Nigel Cox has confirmed the striker's injury will require operating on, which will see Campbell go under the knife on Thursday.
'We have found a stress fracture in the fifth metatarsal of his left foot,' he told the club. 'The fracture doesn't actually go all the way through the bone, so it isn't a fracture in the truest sense of the word, it is more of a crack.
'The consultant we have spoken to has advised us that the best way to deal with this is to put a pin through it.
Blow: Neil Warnock's side have struggled for goals
'He will have surgery on Thursday and will then be placed in an aircast boot for three weeks, which will immobilise the foot.
'The benefit of that is it means there can be some partial weight-bearing, so DJ can put weight on the foot from day one. Once he is out of the boot, and provided he is pain-free, we will push on the rehabilitation from there.
'But, as the manager said, for an injury of this nature you are looking at a timescale of six to eight weeks before the player can resume full training.'
Campbell's injury is a big blow for the west Londoners, who have struggled for goals since their return to the top flight.
Warnock's frustrations were visible after the home draw with Blackburn, where he revealed his fury at 'stupid' lightweight football boots worn by the likes of Campbell.
'I think it is these stupid boots, they're like carpet slippers,' he said. 'Don't talk to me about these boots.
'You can't ban people if they prefer it, but I think they are absolutely stupid boots to wear at the level we're talking about. They give you no support at all, but that's football.'
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