Simmons, a fourth-year junior, has started working out with the defense during player-run practices this month.
Sarkisian said Saturday that he and Simmons agreed that the move would be "a good experiment."
"We are going to look at it in training camp and then probably make a decision after about the first five practices," Sarkisian said.
USC returns defensive line starters Antwaun Woods and Delvon Simmons, but lost All-American Leonard Williams to the NFL. Sarkisian said the decision to test the 6-foot-4, 325-pound Simmons on defense came as a "sheer depth" decision.
"He is a big human being that is hard to move and the more of those guys you have on your defensive front, generally, the better off you are," Sarkisian said.
USC returns all five starters on the offensive line.
Simmons has been sidelined or slowed because of injuries the last three seasons.
Players are not made available to the media during June player-run practices.