Partido Republicano Puro (Pure Republican Party), also known as Partido Constitucional Histórico, was a political party that existed in Puerto Rico from 1924 to 1932. The party's main goal was the annexation of Puerto Rico into the American Union as a state. It resulted from a split of Partido Republicano de Puerto Rico on May 4, 1924. Its president was Rafael Martínez Nadal. The party dissolved in 1932 when it joined members of the conservative end of the Alianza Puertorriqueña to form Partido Unión Republicana (Republican Union Party).