Price, 51, becomes the franchise's 61st manager. He replaces Dusty Baker who was fired after the Reds lost the National League wild-card playoff game to the Pittsburgh Pirates.
Baker managed Cincinnati for six seasons, taking the Reds to the playoffs three of the last four seasons.
Price has never been a manager but he had been considered for the Miami Marlins' managerial post a year ago. Prior to joining the Reds, Price was the pitching coach at Seattle (2000-05) and Arizona (2006-09).
"It's been a heck of a ride to this point, that's for sure, and I know with this job there comes an awful lot of accountability and responsibility," Price said at a news conference.
"One thing I'd really like to accomplish is to make sure that everybody here within the Reds organization, that these are the best years they'll spend in the Reds organization."
The Reds said Price agreed to a three-year contract.
"I have spent a lot of time with Bryan since the season ended and I was convinced after the first meeting he is the right person to help us move this organization forward," Reds General Manager Walt Jocketty said in a team release.
"We've all seen his work here with our pitching staff. He has proven himself to be an excellent communicator and leader and clearly is one of the most respected people not only in our clubhouse but in baseball in general."
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