Tottenham Hotspur winger Adel Taarabt had a long-range shot which Preston goalkeeper Andrew Lonergan got down early to comfortably save in the fourth minute.
He had another snap-shot after nine minutes and Lonergan got a hand to it and parried it into the air and Sean St. Ledger cleared.
Lonergan saved again from Taarabt after 18 minutes.
Taarabt's free-kick found Preston loanee Tamas Priskin and his effort at the back post had no pace on it and Lonergan got down to it fairly comfortably after 21 minutes.
After 28 minutes Preston striker Neil Mellor headed a Kaspar Gorkss header from a Taarabt corner off the line as Lonergan was beaten.
Former Preston left-back Matthew Hill was booked for a foul on Richard Chaplow in the 29th minute.
Mellor beat his man on the right wing and squared low to Jon Parkin, who hit a right-foot shot from deep inside the penalty area that hit QPR goalkeeper Carl Ikeme's near post in the 30th minute.
Darren Carter was booked for fouling Priskin in the 31st minute.
Two minutes later, Lonergan saved from Taarabt low down after Alejandro Faurlin, on QPR's left wing, dispossessed Chaplow and he found Taarabt with a low cross who hit a low shot on the angle.
Right-back Billy Jones made it 1-0 to Preston in the 37th minute from a Chaplow out-swinging right-wing corner to the near post.
Debutant Elliott Ward tried to get on the end of it with his boot and the ball hit a defender and fell into the path of Jones, who smashed the ball into the top right corner of the net from inside the six-yard box.
Chaplow was booked for kicking the ball away in the 41st minute.
Rowan Vine replaced Antonio German at half-time.
Hill and Taarabt had early second-half shots saved.
Gorkss fouled Parkin and referee Andy Haines from Tyne and Wear gave a penalty which captain Callum Davidson hammered home in the 56th minute to make it 2-0.
QPR pulled one back a minute later when Taarabt found Peter Ramage, who grabbed a goal from inside the area into the bottom left corner of the goal.
Chris Sedgwick replaced Carter in the 59th minute.
Mellor had a shot saved after 62 minutes.
QPR made it 2-2 in the 66th minute when Taarabt found Priskin who scored from just inside the area into the bottom right corner of the net.
Rowan Vine's shot was saved a minute later and St. Ledger was booked in the 68th minute.
Chris Brown replaced Parkin in the 71st minute.
Preston's man-of-the-match Lonergan saved man-of-the-match Taarabt's free-kick.
Mellor was booked for a foul on Hogan Ephraim in the 73rd minute.
Taarabt was booked in the 91st minute.
Akos Buzsaky replaced Taarabt a minute later.