Mladic has through his lawyers claimed that he suffers from an incurable disease and only has months left to live.
But a judge in the UN court says that his condition does not meet the requirements of "acute incurable disease" required for a release.
The now 83-year-old Mladic was convicted for his role in the Bosnia war and the genocide in Srebrenica. From July 11, 1995, and onwards, over 8,000 Bosnian Muslim men and boys were massacred by the Bosnian Serb army under the leadership of Mladic.
Mladic, also called "the butcher of Bosnia", was arrested in 2011 and convicted in 2017 by the UN war crimes tribunal in The Hague.
