The 22-year-old delivered another scintillating performance for Mark Warburton’s men against the Bees, although he could not help them to avoid their fifth loss of the campaign.
The Anglo-Nigerian scored his second league goal of the season against Rotherham United on Tuesday and continued their impressive form against the Bees, grabbing an assist in the encounter.
QPR found themselves on the back foot as early as the 14th minute when Vitaly Janelt opened the scoring after he was set up by Rico Henry.
Osayi-Samuel then inspired his side back to contention when he found Lyndon Dykes with a fine pass and the Scotland international swiftly fired his effort beyond the reach of goalkeeper David Raya.
Moments after the hour mark, Ivan Toney scored what turned out to be the winning goal, firing home a fine strike after receiving a timely assist from Emiliano Marcondes.
Four minutes before full time, Queens Park Rangers were reduced to 10 men after Todd Kane received his second caution and was subsequently sent off.
Osayi-Samuel featured for the entirety of the game while Ghana international Tariqe Fosu played for 71 minutes before he was replaced by Sergi Canos.
The defeat saw QPR drop to 13th spot on the Championship table after failing to add to their previous 17 points.
Osayi-Samuel has now made 14 appearances across all competitions for QPR in this term, scoring two goals and providing four assists.
The 22-year-old forward has been a key member for QPR since his arrival at Kiyan Prince Foundation Stadium in 2017.
He will be expected to continue his impressive performances when Queens Park Rangers square off against Bristol City on December 1.