Ballon d'Or winner Benzema has missed four games due to a thigh problem with Les Bleus coach Deschamps naming his 26-man list at 1900GMT later onn Wednesday.
"He has not been able to come back from this little irritation, it is nothing major," Real Madrid coach Carlo Ancelotti told reporters.
"He has tried, but it has not been possible," he added.
Deschamps, who guided France to the 2018 title, is already without injured midfielders Paul Pogba (29) and N'Golo Kante (31).
Experienced centre-back Raphael Varane (29) will not feature before the World Cup for his club Manchester United due to a thigh problem but has not been ruled out of the competition.
Deschamps' side start the defence of their title on November 22 against Australia, before also playing Denmark and Tunisia in Group D.
