DuPree filed qualifying papers Tuesday with the Mississippi Democratic Party.
Before being elected mayor, DuPree started a real estate agency with his wife, served on the Hattiesburg School Board, and was a Forrest County supervisor.
DuPree will be also be in Meridian Thursday as the keynote speaker for an 11 a.m. Dr. Martin Luther King program at Meridian Community College. MCC will be closed on Martin Luther King Day, Jan. 17.
Bill Luckett, a Clarksdale businessman and attorney, filed last week as a Democrat for governor.
Lieutenant Governor Phil Bryant and Pass Christian businessman Dave Dennis have filed for governor as Republicans, and state employee James Broadwater plans to file Friday. Pearl River County supervisor Hudson Holliday also says he'll run as a Republican.
Party primaries are Aug. 2, and the general election is Nov. 8.
Gov. Haley Barbour is limited to two terms and can't run again this year.