The striker joins from FC Metz for an undisclosed fee.
The 23-year-old has signed a three-year deal, after the Hoops agreed a fee with FC Metz, and he becomes the Championship side's fifth signing of the summer.
QPR FC (@QPRFC) August 6, 2016
QPR had to fight off interest from a variety of Premier League and Championship sides in order to bring Ngbakoto to Loftus Road, and his arrival represents a real coup for the club.
Manager Jimmy Floyd Hasselbaink has expressed delight with the club's latest acquisition, telling the R's official website: “I’m delighted we’ve got the deal over the line, there was great interest in him.
“Yeni is a player we’ve scouted for a long while and identified as being a player that suits what we are trying to do here at QPR.
“He’s a good age, he’s already got great quality, but we firmly believe we can help take his game to the next level.
Hasselbaink was full of praise for Ngbakoto, highlighting his attributes and what he can contribute to his new club.
“He’s got a spur of pace that will cause team’s problems, and that is a great asset to have," he continued.
QPR manager Jimmy Floyd Hasselbaink
“He can pick a pass, he can score goals – and if he can get anywhere near to replicating his figures with Metz from last season, we will be delighted.
“I’m really excited to bring him here and I’m sure the fans will really take to watching him play for QPR.”
Ngbakoto made over 200 appearances for FC Metz since making his professional debut in 2010, scoring 54 goals, and he has also represented France at both under-17 and under-18 level.
He also arrives having played a key role in Metz's return to Ligue 1 in the last campaign, contributing 12 goals and 11 assists in 38 games.
Queens Park Rangers manager Jimmy Floyd Hasselbaink
“It has always been a dream of mine to play in England and I believe now is the right time for me to come here and experience playing in another country," Ngbakoto said.
“The manager was really keen for me to come here. He made me feel really wanted and that was a massive factor for me in choosing QPR.”
Ngbakoto's arrival comes just in time for QPR's Championship season opener against Leeds United, but it is unlikely that the Frenchman will make his debut against the Whites.