It has small, leathery, dark-green leaves with a glaucous, densely pubescent underside usually suborbicular to elliptical or lanceolate and are generally spiny to dentate on a younger tree.

[5] As opposed to Quercus ilex, its acorns have a very low level of bitterness tannins and so are generally sweet and a good energy source for livestock.

[9] Quercus rotundifolia is native to most of the Iberian Peninsula (Portugal and Spain), but is also distributed throughout Morocco, especially in the Atlas Mountains, Algeria, Tunisia, southern France (Languedoc-Roussillon) and the Balearic Islands.

[9] The species is threatened by the destruction of its habitat for agriculture, vineyards and pine or eucalyptus plantations.

[1][10] Like other perennial oaks in the Iberian Peninsula, Quercus rotundifolia is also affected by Phytophthora cinnamomi which is becoming more dangerous due to the increased frequency and duration of droughts associated with climate change and, especially in Portugal, a decline for the taxa has been reported.

The inhabitants of the southern Iberian Peninsula 9,000 years ago collected acorns of Q. rotundifolia in autumn (November), gently toasted them in order to preserve them, ground them in granite mills, and consumed the flour in soups or breads.

[5] An apparition of the Blessed Virgin Mary over a Quercus rotundifolia was reported by Francisco and Jacinta Marto and Lúcia dos Santos at Fátima in 1916 and 1917.