The Karl Marx Theater or Teatro Karl Marx is located in the Miramar district of Havana, on First Avenue at tenth street or Calle 10. Originally the Teatro Blanquita, it was the largest cinema in Havana and was built by businessman Alfredo Hornedo in 1949, opening on 30th December that year. The building also contained an ice skating rink. As well as operating as a cinema, it was extensively used as a live theater. In 1956, Liberace appeared on stage as part of his first international tour. It was still operating in 1958. In 1959, after the Cuban Revolution, it was re-named Teatro Karl Marx, and continues as a live theater and concert venue today.

Size-wise the Karl Marx puts other Havana theaters in the shade with a seating capacity of 5500 in a single auditorium. The very biggest events happen here, such as the closing galas for the jazz and film festivals. Cuban singer-songwriters such as Carlos Varela, Silvio Rodríguez and Pablo Milanés are among the notable performers who have graced this particular stage

In 2001, the theater was the scene of a concert by the Welsh rock band Manic Street Preachers, which was attended by President Fidel Castro. On being warned by the band that they would be playing very loud, Castro responded, "You cannot be louder than war!".