In 1954, he graduated from the Faculty of History and Philology of Vilnius University with a degree in Lithuanian language and literature.
Having grown up during the post-war period, Marcinkevičius evokes in his poetry a romanticized version of childhood spent in the Lithuanian countryside, of first love, of man's relationship with nature.
As a poet, he has sought to grasp the essence of national experience and give it fresh artistic expression.
The poet brought back humanistic idea in describing a man, continued on the romantic and lyric poetry tradition, valued the aesthetic side of literature, as opposed to the heroic and propagandistic style of socialist realism.
He has also translated into Lithuanian works of Adam Mickiewicz, Alexandr Pushkin, Sergei Yesenin, Mikhail Lermontov, and the Finnish Kalevala legend.