Christian Carlos Hernan Castillo (born March 28, 1967) is an Argentinian activist, politician, sociologist and university teacher.

He was pre-candidate to Governor of the Buenos Aires Province during the 2015 primary elections, losing to Néstor Pitrola.

[4][5][6] He holds the subject General Sociology in the Faculty of Humanities and Education Sciences of the National University of La Plata, and the optional subject Sociology of revolutionary processes, in the Faculty of Social Sciences of the University of Buenos Aires.

In 2009, he ran as candidate for deputy for the City of Buenos Aires for the Socialist Workers' Left Front conformed by the PTS, the MAS and IS.

He is general coordinator of the Leon Trotsky Center of Study, Research and Publications (CEIP)[8] and regularly collaborates in the "Estrategia Internacional" magazine, which is translated to English and French.