The 6-4, 240-pound defensive end made his decision on national television during the Under Armour All-American Game in Orlando, and picked the Trojans over TCU.
"This was a family decision and I was high on TCU when I took my visit, but based on the family decision and support, I will be continuing my studies at USC," Townsned said. "I'm a Trojan."
"There is just so much talent coming in this year," he said. "I think we have good upside for the future at USC."
The local standout said the chance to stay close to home and play for Ed Orgeron and Monte Kiffin played a big role in his decision to become a Trojan.
"USC was always a no-brainer. Coach O and Monte Kiffin together is just an amazing coaching staff on the defensive side of the ball," Townsend said. "Passing up the chance to get coached up by Coach O and my dad, you're stupid.
"You don't get homesick, so that's the best part about it. All the guys that I grew up with can come and watch me and USC fans are great. I feel great about this decision."
Townsend is yet another piece in an already talented defensive line group that includes Jalen Grimble and Antwaun Woods among others.
"We always talk about being the Wild Bunch 3," Townsend said.
Greg Townsend battles Christian Westerman during Under Armour practice.
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