The 64-year-old Delaware lawmaker said he will file paperwork with the Federal Election Commission and launch a campaign Web site, joebidenforpresident.com.
He joins a crowded Democratic field dominated thus far by New York Sen. Hillary Rodham Clinton and Illinois Sen. Barack Obama. Other candidates include former North Carolina Sen. John Edwards, the 2004 vice presidential nominee; Connecticut Sen. Chris Dodd, New Mexico Gov. Bill Richardson, former Iowa Gov. Tom Vilsack, and Ohio Rep. Dennis Kucinich.
Biden traveled extensively last year to the early voting states of Iowa, New Hampshire and South Carolina and plans another swing through those states soon after launching his presidential committee, said his spokesman, Larry Rasky.
As the new chairman of the Senate Foreign Relations Committee, Biden recently convened several weeks of high-profile hearings on the Iraq war.
Generally regarded as a long shot in the presidential contest, Biden is one of his party's leading spokesmen on foreign affairs and plans to stress that expertise on the campaign trail. Biden voted in 2002 to authorize military intervention in Iraq, but has since become a vociferous critic of the conflict.
Biden has also criticized President Bush's plan to deploy an additional 21,500 troops to try and stabilize Iraq's capital city, Baghdad. On Wednesday, the Foreign Relations Committee approved a resolution he co-authored with Sens. Carl Levin, D-Mich., and Chuck Hagel, R-Neb., stating that sending more troops into Iraq is "not in the national interest."
Biden has also been promoting a detailed plan for peace in Iraq that would divide the country along ethnic lines.
This is not the first time Biden has sought the presidency. He was a candidate for the 1988 Democratic presidential nomination, but withdrew from the race in 1987 amid accusations that he had plagiarized passages in his speeches.
Biden has about $3 million in his Senate campaign account that will transfer to his presidential committee, Rasky said.
The campaign will be run by Luis Navarro, a longtime Democratic activist with close ties to organized labor. Recently, Navarro headed the Florida Democratic Party and served a stint as political director for Massachusetts Sen. John Kerry's failed 2004 presidential bid.