Isolina Rondón (April 11, 1913 – October 2, 1990) was a political activist. She was one of the few witnesses of the killing of four Nationalists committed by local police officers in Puerto Rico during a confrontation with the supporters of the Nationalist Party that occurred in October 24, 1935, and which is known as the Río Piedras massacre. Rondón joined the political movement and became the Treasurer of the Puerto Rican Nationalist Party which staged various uprisings in Puerto Rico against the colonial Government of the United States in 1950.