Studied at the Academy of Fine Arts in Warsaw, and graduated from poster art under professor Henryk Tomaszewski and from painting under professor Teresa Pagowska.

He is currently the principal communication designer in his own studio whose work ranges from graphic design to illustration, and has a close relationship with the community, culturally and art wise. The works of the studio are widely published and exhibited around the world.

He is the co-founding member of Brumen Foundation organizer of the Slovene biennials of visual communication. He is also the founder and art director of The Poster Festival Ljubljana. Since 1991, Jenko has been a professor of Visual communications at the Academy of Fine Arts and Design, Ljubljana, Slovenia. AGI member since 2013.