Officers received a call about a loud party at the apartment of former Tennessee linebacker Dontavis Sapp, 22, who was also taken into custody with Johnson, 22, and O'Brien, 20, the Knox County Sheriff's Office said.
Johnson, a first-team all-Southeastern Conference selection last season, was charged with purchasing alcohol for a person underage and resisting arrest. O'Brien, a reserve nose tackle as a redshirt freshman last season, was charged with criminal impersonation, resisting arrest and underage consumption of alcohol.
O'Brien "had a very strong odor of alcohol on his breath and became combative" as an officer tried to take him into custody, according to the arrest report, which did not provide details about the other arrests.
Sapp was also charged with resisting arrest and buying alcohol for a person underage.
All three have been released. The players phone numbers were unlisted and it's unclear if they have attorneys.
Tennessee coach Butch Jones said in a statement he's aware of the situation and is gathering facts.
"We have very high standards and expectations within our football program at the University of Tennessee, and appropriate action will be taken," he said.
Johnson made a team-high 106 tackles last fall in his third season as a starter. He had 138 tackles in 2012 and ranked fourth among all Football Bowl Subdivision players with 11.5 tackles per game. Johnson announced last month he would return for his senior season rather than entering the NFL Draft.
O'Brien made 12 tackles and played in all 12 games in a reserve role as a redshirt freshman last season. Sapp closed his career last fall by starting 12 games and making 66 tackles.