Gojira's sound is not easily classifiable as they blend several styles. Genres that have been associated with Gojira are technical death metal, progressive metal, groove metal and thrash metal. Gojira has been influenced by heavy metal artists such as Slayer, Sepultura, Death, Morbid Angel, Meshuggah, Tool, Metallica, Pantera, and Neurosis.
Gojira's lyrics tackle themes of life, death, rebirth, spirituality, and nature. In particular, their 2005 album From Mars to Sirius is a concept album tackling environmental issues as well as broader themes of life, death, and rebirth like on ‘The Way of All Flesh’.