The name derives from a Romanian word of Slavic origin (žilav, which passed into Romanian as jilav) meaning "humid place". Jilava was the location of a fort built by King Carol I of Romania, as part of the capital's defense system. At a later date, the fort was converted into a prison.
This prison is the site where, on November 26-27, 1940, the Iron Guard authorities of the National Legionary State killed 64 political prisoners as revenge for the previous killing of their leader Corneliu Zelea Codreanu (see Jilava Massacre); it was also here that Ion Antonescu, dictator (Conducător) of Romania during World War II, was executed for war crimes in 1946. The prison also was detention site for political prisoners after the start of Communist rule in Romania.
It is a functioning prison today.