Brennan Armstrong (born October 18, 1999) is an American professional football quarterback who is a free agent.

As a redshirt junior, Armstrong led Virginia to the Wasabi Fenway Bowl which was canceled due to COVID-19.

[5] In a game against Georgia Tech he led the offense after starting quarterback Bryce Perkins went down with an injury.

[6] He completed one of his two pass attempts going for a 56 yard touchdown for the first of his career to wide receiver Joe Reed.

He missed five games against Florida State, Old Dominion, Notre Dame, and Miami due to an injury.

[11] He completed one pass against North Carolina on a fake field goal to Tanner Cowley for five yards that led to a touchdown.

[13] In Armstrong's redshirt sophomore season, he was named as one of Virginia's four team captains along with Richard Burney, Terrell Jana, and Charles Snowden.

15 North Carolina, Armstrong led the team to an upset win in which he threw for 208 yards and an additional three touchdowns in the 44–41 victory.

[30] The team would finish of the year with a 15–33 loss to Virginia Tech,[31] in that game Armstrong threw for 259 yards and two touchdowns.

[32] In Armstrong's redshirt junior season, he was once again voted as team captain alongside Mandy Alonso, Nick Jackson, and Wayne Taulapapa.

[36] Against North Carolina, Armstrong set another Virginia record when he threw for 554 yards against the Tar Heels,[37] which at the time was also the highest of the season up to that point.

[40] In a game against BYU he suffered an injury after accounting for a total of six touchdowns in the team's 49–66 loss.

[41][42] In that game he broke the school's record for passing yards with an eight-yard completion to tight end Jelani Woods.

[54][55] The next week he broke the school's career passing yards record with a seventeen yard completion to Lavel Davis Jr.[53] Two weeks later he broke another one of Schaub's records as he threw for his 21st 200-yard game against Duke despite the team's loss.

On May 10, 2024, the Jacksonville Jaguars announced Armstrong would participate in their rookie camp as a tryout player.