Madlenianum Opera and Theatre is the first privately owned opera and theater company both in Serbia and in south-eastern Europe. It is located in Belgrade, Serbia, and was founded on 26 January 1999, by Madlena Zepter, wife of the Philip Zepter, Serbian businessman. The name Madlenianum derives from Madlena Zepter's name.
Madlenianum was officially founded on 25 December 1997, while first performance on 26 January 1999 marks theater public revelation. Madlenianum is located in the building that previously housed second stage of National Theatre of Serbia. After seven years of work and five different stages of reconstruction, on 19 April 2005, a completely refurbished, reconstructed and conceptually enriched edifice opened its doors to the public. It is situated in the Old city core of Zemun, which is Spatial Cultural-Historical Units of Great Importance of Serbia. Theatre housed opera, ballet, concert program, drama and musical repertoire.