David McGoldrick's second-half goal secured a point for the visitors, who went behind to Mikele Leigertwood's brilliant strike.
Leigertwood scored on 26 minutes with a left-footed shot from 30 yards that flew past former QPR goalkeeper Lee Camp and into the corner of the net.
The breakthrough came after Forest had started well and would have taken an early lead had Rangers keeper Radek Cerny not produced a fine double save.
Radoslaw Majewski raced on to McGoldrick's flick on and after parrying the Polish midfielder's shot, Cerny quickly got to his feet and kept out Joe Garner's follow-up.
And Rangers had a lucky escape when McGoldrick slipped away from defender Damion Stewart to collect Majewski's pass, before sending a right-footed shot wide of the far post.
Majewski smashed over as Forest continued to trouble Rangers, who finally came to life and should have scored when Adel Taarabt hurriedly shot wide after being found in acres of space by Heidar Helguson.
Gary Borrowdale also missed a chance to put QPR ahead by blazing over following Wayne Routledge's cross but in Rangers' next attack, Leigertwood found the net in spectacular fashion.
But Forest equalised 12 minutes into the second half. Camp's long kick was flicked on by Dele Adebola and McGoldrick sneaked between defenders Borrowdale and Kaspars Gorkss to fire home.
Rangers boss Jim Magilton responded by sending on crowd favourites Akos Buzsaky and Rowan Vine, who both brought saves from Camp after coming on.
Helguson missed QPR's best chance of a winner when he headed over from Buzsaky's right-wing cross.