Nicolás Sartorius (San Sebastián, 1938) is a Spanish lawyer, politician and essayist. His activism began when he was studying law at the Complutense University of Madrid, shortly before joining the Spanish Communist Party. During the Franco dictatorship he was arrested and convicted on several occasions due to his political stance, and was one of the defendants in the so-called Trial 1001. He co-founded the workers' union Comisiones Obreras, was a deputy for the PCE and IU for three terms, becoming parliamentary spokesman for the coalition until 1993. He is the author of various books and articles on topics such as socialism, unionism, the dictatorship, the transition and language in politics.