Orlovsky led the Indianapolis Colts to their only two victories of 2011 after being elevated to the starting job late in the season.
Last season, in his first action since 2008 when he started seven games for the 0-16 Detroit Lions, Orlovsky completed 122 of his 193 pass attempts (63.2 percent) for 1,201 yards with six touchdown passes and four interceptions.
He is the fourth player signed by the Buccaneers since free agency began Tuesday. The Bucs entered free agency more than $42 million under the league salary cap and have made a big splash, signing All-Pro guard Carl Nicks, two-time Pro Bowl receiver Vincent Jackson and well-regarded cornerback Eric Wright to contracts totaling more than $140 million.
Information from The Associated Press was used in this report.