The New York medical examiner identified the man as Patrice Braut, 31-years-old at the time of the attacks.
Braut was identified by new DNA tests conducted on human remains recovered during operations in the World Trade Center ruins in 2001 and 2002.
Only 60 percent of the 2,753 people missing and believed dead in the New York attacks have been formally identified.
Medical examiners are examining 21,906 groups of human remains found at the site of the collapsed World Trade Center in the search.
Tests continue on the remains and developments in science in recent years have helped make new identifications.