Valentín Ferraz y Barrau (Huesca, Spain, 1792 – Madrid, Spain, 1866) was a Spanish military commander and politician.
After fighting in the Peninsular War and in the Peruvian War of Independence Valentín engaged in the chaotic politics of the post-war reign of Isabella II of Spain, serving as Prime Minister of Spain in 1840 and holding other important offices such as Mayor of Madrid.
Born into a noble family established in the twelfth century around the Benasque Valley, Huesca, the family produced several illustrious clerics, politicians, lawyers and military strategists.
He was the nephew of Antonio Cornel y Ferraz, the Spanish Minister of War for Charles IV of Spain and first cousin of Jose Ferraz y Cornel, Spanish Minister of Finance For Queen Isabella in 1840, and Francisco Javier Ferraz y Cornel, Lieutenant General and Chief Military Justice, also during the reign of Isabella II.