Saline minerals are widely distributed in Spain, particularly in the eastern half of the country. Deposits are in rocks of the Triassic–Early Liassic, late Eocene–Oligocene, and Miocene. Although saline minerals occur in Permian rocks, they are not as well developed as they are in the Permian of northern Europe. The principal deposits are in the Keuper and occur over much of eastern Spain. Rock salt occurs extensively in the subsurface Keuper; outcrops consist of gypsum and marl.

The Keuper salt forms salt chimneys or salt domes in the Cantabric trough. Fourteen intrusions are known, and they involve a large volume of sedimentary rock. Original salt movement is believed to be due to gravitational tectonics, later modified by the Hercynian and other orogenies. Salt domes also are known in Andalusia and in the Betic chains. The Keuper also provided the lubricant for gliding and intense folding in the Pyrenees. The salt domes of the Cantabric trough rise through 7000 m or more of sedimentary rocks and are in places exposed, providing spectacular exhibits of diapiric folds.

The saline deposits have been extensively exploited for rock salt and brine. Potassium salts and sodium sulphate also have been recovered in limited amounts.