One person was in critical condition after the early Sunday shooting, said New Orleans police spokesman Frank Robertson. Seven others were hospitalized in stable condition. The remaining victim's condition was not available.
The victims were shot just two blocks from historic Jackson Square and just around the corner from the popular Pat O'Brien's piano bar.
An investigation is ongoing. Robertson said no arrests have been made, and no suspects have been identified. Robertson said other details will be released when they become available.
New Orleans Mayor Mitch Landrieu on Sunday pledged a swift law-enforcement response.
"Our No. 1 priority is to keep New Orleans safe," Landrieu said in a statement issued through City Hall spokesman Tyler Gamble. "These kinds of incidents will not go unanswered ... I am confident that between video evidence and eyewitness accounts, we will bring the perpetrators to justice."
Sunday morning's incident is the third major shooting on Bourbon Street in the last three years.
Last February on the Saturday before Mardi Gras, four people were treated at a hospital after a shooting. During Halloween in 2011, one person was killed and seven others were injured after gunmen opened fire on each other.
Michael Tilbury, who lives a few blocks from the shooting, told NOLA.com/The Times-Picayune (http://bit.ly/1mvaejx) he heard the early morning shots.
"The shots woke us up," Tilbury said. "We've lived here for two years, never heard or seen anything like this."
Bourbon Street is New Orleans' most famous street, a nightly swirl of bright neon and happy tourists with beverage in hand. A blend of jazz joints, strip clubs, bars and restaurants, Bourbon Street has everything from four-star dining to sex shows.
Built on higher ground than most of the city, the French Quarter was spared the worst of Hurricane Katrina in 2005, mostly suffering scattered wind and water damage.