The Altiplano Potosino-Zacatecano (Potosino-Zacatecano Highlands) is home to relict oak groves. Species of the genus Quercus are important ecologically, socially and economically. However, information about their richness and distribution is scarce. Therefore, the aim of this study is to determine the richness and distribution of Quercus species in four mountain ranges and two isolated hills of the Altiplano Potosino-Zacatecano. The oak groves were delimited using field-verified cartographic information. From March to July 2014 and from January to April 2015, 85 specimens were collected, identified and compared with collections held by the Universidad Autónoma de San Luis Potosí, the Universidad Nacional Autónoma de México and the Universidad Autónoma de Aguascalientes. Ten Quercus species were recorded. Only Q. tinkhamii, Q. potosina and Q. eduardii had been previously reported for the region, specifying the location. Of the others, two were found in Peñón Blanco, three in Guanamé, two in Sierra la Mojonera, one in Cerro Los Licenciados and one in Sierra de San Miguel. Q. saltillensis is a new record for the study area. Q. jonesii and Q. greggii are located in Cerro Peñón Blanco, Q. eduardii, Q. striatula, Q. pringlei in Sierra de Guanamé and Mesa la Difunta, and Q. grisea in Cerro Los Licenciados and Sierra San Miguel. Quercus saltillensis is a new record in Sierra de Guanamé, Venado, S.L.P.