The 20-year-old right-back, who joined Rangers on an initial one-month deal, will now stay at Loftus Road until January 3.
Walker has impressed during five appearances so far as Neil Warnock’s leaders have maintained their unbeaten start to the npower Championship season.
Walker made the move from north to west London last month as cover for first choice right-back Bradley Orr who was sidelined with a calf injury.
And former Sheffield United boss Warnock has been so impressed by Walker - also a former Blade - that he wants to keep him at Loftus Road for a longer period, despite Orr's imminent return to full-fitness.
"Kyle's a great player who can play at left-back, or in Shaun Derry's position, or at centre-back, so he’s got a few strings to his bow," said Warnock.