The striker scored five goals in two games to help the west London club win back-to-back games for the first time in its Premier League first season.
In the 85th minute, Christian Eriksen, who had just started his second match since coming in January, lifted in a cross for Toney to head home. After being hauled down by Nathan Collins, who was sent off, Toney scored from the penalty spot in the fourth minute of stoppage time. Brentford is nine points clear of Burnley in the relegation zone. Toney clinched the victory from the penalty spot.
Burnley would have moved out of the bottom three for the first time this season if they had won, but Jay Rodriguez was stopped by the goal frame as they drew another blank