Karim Benzema is sidelined with a thigh injury suffered playing for Real Madrid, while Juventus midfielder Paul Pogba faces a race against time to be fit for the World Cup after undergoing knee surgery.
With Chelsea's N'Golo Kante recovering from injury, Paris Saint-Germain defender Presnel Kimpembe sidelined, and Bayern Munich duo Kingsley Coman and Lucas Hernandez also ruled out, Deschamps has brought back some familiar faces and handed a first chance to others for France's games against Austria and Denmark later this month.
Giroud, who will be 36 come the World Cup in Qatar, is rewarded for a fine start to the season at AC Milan with a recall, while Dembele comes into the squad for the first time since June last year, when he limped out of the European Championship.
There are first call-ups for the Eintracht Frankfurt striker Randal Kolo Muani as well as Monaco centre-back Benoit Badiashile and his club colleague Youssouf Fofana.
Kylian Mbappe, Antoine Griezmann and goalkeeper Hugo Lloris are among the six players in the squad who featured in the 2018 World Cup final win over Croatia.
France host Austria in Paris on September 22 before playing Denmark in Copenhagen three days later.
While the matches serve as preparation for the World Cup, which starts on November 20, France are currently bottom of Nations League A, Group 1 so need points from their final two games to avoid relegation to League B.
They won the last edition of the Nations League last year.
Goalkeepers: Alphonse Areola (West Ham United/ENG), Hugo Lloris (Tottenham Hotspur/ENG), Mike Maignan (AC Milan/ITA)
Defenders: Benoit Badiashile (Monaco), Jonathan Clauss (Marseille), Theo Hernandez (AC Milan/ITA), Jules Kounde (Barcelona/ESP), Ferland Mendy (Real Madrid/ESP), Benjamin Pavard (Bayern Munich/GER), William Saliba (Arsenal/ENG), Dayot Upamecano (Bayern Munich/GER), Raphael Varane (Manchester United/ENG)
Midfielders: Eduardo Camavinga (Real Madrid/ESP), Youssouf Fofana (Monaco), Matteo Guendouzi (Marseille), Adrien Rabiot (Juventus/ITA), Aurelien Tchouameni (Real Madrid/ESP)
Forwards: Ousmane Dembele (Barcelona/ESP), Olivier Giroud (AC Milan/ITA), Antoine Griezmann (Atletico Madrid/ESP, on loan from Barcelona/ESP), Randal Kolo Muani (Eintracht Frankfurt/GER), Kylian Mbappe (Paris Saint-Germain), Christopher Nkunku (RB Leipzig/GER)