José Antonio Primo de Rivera y Sáenz de Heredia, 1st Duke of Primo de Rivera, 3rd Marquis of Estella GE (24 April 1903 – 20 November 1936), often referred to simply as José Antonio, was a Spanish national syndicalist politician who founded the Falange Española ("Spanish Phalanx"), later Falange Española de las JONS.
José Antonio was the eldest son of General Miguel Primo de Rivera (2nd Marquess of Estella), who governed Spain as dictator from 1923 to 1930. He worked as a lawyer from 1927 to 1933 before entering politics through the National Monarchist Union, an enterprise he initially engaged in because of his vows to defend his recently deceased father's memory. After becoming disillusioned with the traditionalist monarchist policies, he founded the short lived Movimiento Español Sindicalista alongside Julio Ruiz de Alda. Soon after he founded Falange Española in October 1933, shortly before running as a candidate in the 1933 general election, in which he won a seat in the Congress of Deputies of the Second Spanish Republic.