In this study, we analyse, first, what competences regarding environmental sustainability are envisaged in the curricula of primary teachers at Spanish universities and, second, to what extent these competences guide the aims and content of the subject matter and the topics in the syllabi. From an analysis of the 79 competences which, according to ministerial regulations, should direct primary teacher training, three are directly related to environmental sustainability. The analysis of the content of the curricula from a sample made up of 23 Spanish universities indicates that these three competences have been taken into account in all of them, and that in 73% of the curricula other competences directly related to environmental sustainability are also incorporated. In a few cases, however, their degree of precision is vague. In only 26% of the curricula studied is a specific subject of environmental education--always optional--envisaged, and this topic is where the main educational efforts regarding sustainability are focused. In the absence of studies that analyse other more detailed curricular planning documents, the curricula of future primary teachers in Spain does not seem to ensure good training with respect to environmental sustainability.