Cardiff created most of the first-half chances, with Joe Ledley firing wide and Cameron Jerome having a header blocked by defender Danny Shittu.
QPR's Gareth Ainsworth had a free-kick saved after the break and then Marc Nygaard was denied from close range.
Paul Furlong also tested home keeper Neil Alexander before Cardiff's Kevin Cooper fired a long-range effort wide.
QPR caretaker boss Gary Waddock:
"It was a good point and at one stage I thought it could have been all three.
"We came to win and had more opportunities to score in the second half when the play opened up.
"We passed it well and made several chances but I was never going to approach this game in cavalier style."
Cardiff: Alexander, Barker, Purse, Loovens, Scimeca, Ardley, Koumas, Ledley, Cooper (Weston 77), Thompson, Jerome.
Subs Not Used: Cox, Boland, Ndumbu-Nsungu, Worgan.
QPR: Jones, Bignot, Milanese, Evatt, Shittu, Bircham, Ainsworth, Cook, Lomas, Youssouf (Furlong 72), Nygaard (Langley 89).
Subs Not Used: Royce, Santos, Baidoo.
Ref: K Wright (Cambridgeshire).