USF had not won a road game against a ranked opponent since Notre Dame in 2011, as they now improve to 2-0 on the season while the Gators fall to 1-1 following their 18-16 stunning victory.
They were 18.5-point underdogs heading into the matchup.
After being down 9-6 at halftime, USF held the Gators scoreless in the third quarter and came out with a fire lit under them.
They forced the game's only turnover after cornerback James Chenault brought in his first interception of the season.
However, despite being forced to punt following the interception, the USF defence made sure to hold on and it all paid off perfectly.
Quarterback Byrum Brown completed a 66-yard touchdown to wide receiver Keshaun Singleton to go up 13-9 before adding another two on the board with a safety shortly after.
But Florida wouldn't go away.
Quarterback DJ Lagway completed a four-yard touchdown Eugene Wilson III to retake the lead 16-15.
Then, after a couple punts between both teams, USF drove down the field to give kicker Nico Gramatica a chance to go up 18-16 with a 58-yard field goal - but he missed.
But shortly after, the Bulls got the ball back and made sure to give Gramatica the easy kick he could possibly have from 20 yards in the middle of the field.
USF finished the game with 391 total yards to Florida's 355. Both teams combined for 20 penalties (USF-9, UF-11) while the Gators dominated in time of possession 34:13 - 25:47.
USF went 6-16 on third down while Florida went 4-12.
The Bulls have now won back-to-back ranked opponents (#24 Boise State, #13 Florida) and are now heading to another brutal matchup against the No. 5 Miami Hurricanes on September 13th.
Meanwhile, Florida will also be heading into a tough matchup on September 20th as they prepare for No. 3 LSU.