Mathias Malzieu (born 1974) is the lead singer of the French band Dionysos, which he co-founded in 1993 when he lived in Valence in Drôme (Auvergne-Rhône-Alpes). Three of his schoolfriends, Eric Serra Tosio, Michael Ponton and Guillaume Garidel, were among the band's original members.

Malzieu has written the following books:

• 38 mini westerns avec des fantômes (2002)
• Maintenant qu'il fait tout le temps nuit sur toi (2005)
• La mécanique du cœur (2007); English translation titled The Boy with the Cuckoo-Clock Heart released in September 2009
• Métamorphose en bord de ciel (2011)^[1]
• Le Plus Petit Baiser Jamais Recensé (2013)
• Journal d'un vampire en pyjama (2016); English translation titled Diary of a Vampire in Pyjamas released in May 2017
• Une sirène à Paris

• Le dérèglement joyeux de la métrique amoureuse

With Stephanie Berla, he directed Jack and the Cuckoo-Clock Heart, for which Dionysos composed music and in which he voiced Jack, and A Mermaid in Paris.