The report, issued Tuesday, charged inadequate coordination and communication by the domestic intelligence agency DCRI allowed Mohamed Merah to kill a rabbi, three school children and three soldiers, France 24 reported.
Merah died March 22 at his home in Toulouse in a gun battle with police.
The 17-page document said failures by DCRI "go beyond the simple scope of human error, rather, they consist of a conjunction of omissions, faulty judgment, management problems, poor organization of services and ever-present divisions between intelligence, police and public safety."
Six areas where intelligence operations could be improved were identified by the report.
Investigators found Merah was first noticed by the intelligence community in 2006, but didn't attract attention again until DCRI learned in December 2010 he had visited Afghanistan. An investigation of Merah was requested in January 2011, and he was put under surveillance for six months.
Intelligence officers in Toulouse documented Merah's affinity for jihadist groups and his suspicious behavior but he was able to visit Pakistan undetected in August 2011 where he is believed to have gone to a terrorist training camp.