Gourcuff and Montpellier centre-back Mapou Yanga-Mbiwa were dropped from a preliminary list of 25 as Blanc decided to travel to Ukraine with seven defenders and no recognised playmaker.
Gourcuff had been named in a preliminary squad in spite of a mediocre domestic season, but he failed to impress in a 3-2 friendly win against Iceland on Sunday.
France, instead, will rely on speed down the flanks with Jeremy Menez, Franck Ribery and Mathieu Valbuena all named.
Yanga Mbiwa, who marshalled the Montpellier defence to their maiden Ligue 1 title this season, was one of four centre-backs and there was little surprise that Blanc dropped the 23-year-old, who had never been called up before.
Blanc had initially called up centre-back Younes Kaboul and forward Loic Remy but lost both players to injuries.
France have been drawn in Group D against England, co-hosts Ukraine and Sweden in the June 8-July 1 tournament.
Les Bleus, who are unbeaten in their last 19 games, will start their campaign against England in Donetsk, Ukraine, on June 11.
Squad:
Goalkeepers: Hugo Lloris (Olympique Lyon), Steve Mandanda (Olympique Marseille), Cedric Carrasso (Girondins Bordeaux).
Defenders: Gael Clichy (Manchester City), Patrice Evra (Manchester United), Laurent Koscielny (Arsenal), Philippe Mexes (AC Milan), Adil Rami (Valencia), Mathieu Debuchy (Lille), Anthony Reveillere (Olympique Lyon).
Midfielders: Yohan Cabaye (Newcastle United), Florent Malouda (Chelsea), Samir Nasri (Manchester City), Alou Diarra (Olympique Marseille), Yann M'vila (Stade Rennes), Marvin Martin (Sochaux), Blaise Matuidi (Paris Saint-Germain).
Forwards: Hatem Ben Arfa (Newcastle United), Karim Benzema (Real Madrid), Franck Ribery (Bayern Munich), Olivier Giroud (Montpellier), Jeremy Menez (Paris Saint-Germain), Mathieu Valbuena (Olympique Marseille).
