Nagin, a Democrat who served two terms as mayor, was acquitted on one count but faces as much as 20 years in prison following his conviction on charges of taking more than $500,000 and free travel from contractors in exchange for helping them get contracts worth millions of dollars, NBC News said.
Prosecutors said the corruption began before Hurricane Katrina devastated New Orleans in 2005 and persisted as the city and the region recovered from the storm.
Nagin, 57, who served as mayor from 2002 to 2010, denied taking bribes. He was also convicted of filing a false tax return, among other counts.
Prosecutors presented testimony by business executives convicted in the investigation, as well as documentation of payments and contract awards they said showed Nagin was "on the take," the (New Orleans) Times-Picayune reported.
U.S. District Judge Ginger Berrigan ordered Nagin be placed under house arrest until he is sentenced, NBC said.