Marko Japelj, the author of the stage designs for almost three hundred productions, studied architecture in Ljubljana. His first work was stage design of Ibsen's drama Hedda Gabler for the Theatre and Film Academy in Ljubljana. His scenography debut on the professional stage was the design for the production of Chekhov's play The Three Sisters at the Slovenian National Theatre in Maribor (1987).

He has created stage designs for opera, ballet and drama productions for the Slovenian National Theatres in Ljubljana and Maribor, the Croatian National Theatre in Zagreb and the Croatian National Theatre of Ivan Pl Zajc in Rijeka, the National Theatre in Belgrade, and the Montenegrin National Theatre in Podgorica, National Theatre in Brno, National Opera in Bucharest, Zürich Opera, Aalto-Musictheatre in Essen, Latvian National Opera, Opéra-Théâtre de Metz, Vienna State Opera, Leipzig Opera, Novosibirsk State Academic Opera and Ballet Theatre (NOVAT) and Bolshoi Theatre in Moscow. He has worked with companies such as the Royal Flemish Ballet, Netherlands Dance Theatre 1 (NDT 1), West Australian Ballet, Les Grands Ballets Canadiens de Montréal, Birmingham Royal Ballet and companies in Darmstadt, Wiesbaden, Wuppertal, Augsburg, Dortmund, Stuttgart and others.

He has collaborated with the choreographer Edward Clug on Tango, Lacrimas, Radio&Juliet, Architecture of Silence, Pret-a-porter, Watching others, Hill Harper's Hill, Chamber Minds, Sacre du Printemps, Les Noces, Peer Gynt, Hora/Kontraste, Proof, Kekec, Petrushka, Patterns in ¾, Carmina Burana, Aperture, Source, The Master and Margarita.

He has received many awards for his work, such as the National Award Prešeren Fund. He has been awarded the prize for the best scenography at the National Festival in Borštnik, at the MES Festival in Sarajevo, at the Rijeka Festival and the Crossroad Festival in Niš, Serbia several times.

He was a Professor and Head of the Department of Theatre and Film Scenic Design at the University of Applied Arts in Vienna (Universität für Angewandte Kunst Wien).