Wigan were missing seven players through either suspension or injury, while an eighth, playmaker Shaun Maloney, was only fit enough for the bench.
It was the Latics' first point in three games but manager Roberto Martinez felt they deserved more.
He said: "We are disappointed because to concede two goals is always frustrating. I just feel that for us to score a goal we need to be perfect.
"And the first time that QPR get in our box they get a free header and then in the second half they didn't have an attacking threat but they got in front. But I was very pleased with the manner in which we reacted to going 2-1 down.
"It would have been all too easy to panic, to lose our composure but I thought we were very mature and we're disappointed that we couldn't get any more because the chances were there.
"I thought Robert Green had an outstanding performance and in many ways I thought we deserved the three points."