"I'm highly concerned for our franchise and for Ben personally," Tomlin told the NFL Network after arriving in Orlando, Fla., on Saturday for the NFL meetings, which start Monday.
The police in Milledgeville, Ga., are still investigating a 20-year-old female college student's accusation against Roethlisberger.
"My concerns are many," Tomlin said, "but I think at this time it's kind of appropriate to watch these things and let these things run their course. I think it would be inappropriate for me to have strong feelings one way or another with the investigation being ongoing and so forth. Like everyone else, you watch these things unfold."
The woman accused Roethlisberger, 28, of sexually assaulting her in a Georgia nightclub earlier this month.
Roethlisberger also faces a lawsuit filed last July by a woman who says he raped her in 2008 at a Lake Tahoe hotel and casino, an allegation he strongly denies.
Roethlisberger, who was not in custody, has not been criminally charged in either case and has claimed counter-damages in the lawsuit.