This vegetation study describes the plant associations of El Vizcaíno Biosphere Reserve (Baja California, Mexico) as determined by the Braun-Blanquet method and supported by cluster analysis. Twenty-two associations were identified, 7 of which are described for the first time (Camissonio crassifoliae-Encelietum ventori, Encelio phenocodontae-Atriplicetum polycarpae, Lycietum brevipedis, Errazurizio benthamii-Pachycormetum veatchianae, Merremio aureae-Lysilometum candidae, Opuntio taponae-Burseretum microphyllae, and Suaedo taxifoliae-Allenrolfeetum occidentalis). Ecological, biogeographical, bioclimatic, and floristic data are provided for each of these new associations.