Otto married Adelheid of Vianden, daughter of Philip of Vianden and Adelheid of Arnsberg. They had four children:
Adelheid of Nassau, who became a nun at Keppel, and later became an Abbess. Johan I of Nassau who married Margareta von der Marck.
Heinrich "the Swashbuckler" (died 5 September 1402 in Kassel) became a Canon at the Cologne Cathedral.
Otto of Nassau, first a canon and provost of Saint Moritz at Mainz, and later canon at Cologne and Mainz cathedrals.