Sarmiento was born in Carrascal, a poor suburb of San Juan, Argentina on February 15, 1811. His father, José Clemente Quiroga Sarmiento y Funes, had served in the military during the wars of independence, returning prisoners of war to San Juan. His mother, Doña Paula Zoila de Albarracín e Irrázabal, was a very pious woman, who lost her father at a young age and was left with very little to support herself. As a result, she took to selling her weaving in order to afford to build a house of her own. On September 21, 1801, José and Paula were married. They had 15 children, 9 of whom died; Domingo was the only son to survive to adulthood.
At the age of four, Sarmiento was taught to read by his father and his uncle, José Eufrasio Quiroga Sarmiento, who later became Bishop of Cuyo. Another uncle who influenced him in his youth was Domingo de Oro, a notable figure in the young Argentine Republic who was influential in bringing Juan Manuel de Rosas to power.