Our knowledge of the religion and cosmology of the Maya results mostly from the codices, the books of Chilam Balam, a collection of Yucatec manuscripts and the Popol Vuh, the book of the Community which is a Quiché document. The Maya pantheon was very rich and included a large number of deities which are described in detail in this chapter. Archaeological and historical texts support the ubiquity of religious practices including the offering of blood which was frequent in Mesoamerica before the arrival of the Spanish. The Maya made pilgrimages at all times of the year and to multiple locations. Certain places were considered naturally sacred: this was the case of caves, mountains, islands, ruins and cenotes, these collapsed dolines in karst environments. In the cosmology of the Maya, the universe, in its entirety, is described in accordance with a vertical conception, it appears in the form of a cosmogram with the underworld in the lower part, then the Earth and finally the sky in the upper area. We also find, in the books mentioned, the sources of the myths of the creation of the universe and the description of the story of the Twin Heroes which was of major importance in the eyes of this people. The main contributions of famous archeologists or explorers like Tozzer, Maudslay, Maler or Seler are also described in this chapter.