The club insist the 27-year-old will not leave unless their valuation is met after the striker struggled to secure a regular first-team place under Harry Redknapp last season
The 27-year-old scored two goals in 29 Premier League appearances last season as Harry Redknapp's side suffered relegation from the Premier League.
QPR claim the decision is based on the Mackie's restricted first-team opportunities but insist they will not sell the striker until their price has been met.
"Jamie Mackie has today submitted a transfer request, which the club have reluctantly accepted," read a statement from QPR.
"The 27 year-old has informed the club of his desire to leave, having found first team opportunities limited at Loftus Road in the last six months.
"As previously stated, no player will leave QPR unless the club’s valuation is met."