He attended the Real-Gymnasium in Braunschweig and the Wolterstorffsche Institut in Ballenstedt, after which he completed a commercial apprenticeship in Hanover.
In the same year, Ralfs held his first exhibition of "modern art" paintings at the then Landesmuseum (now the Herzog Anton Ulrich Museum).
These visits resulted in his "famous guest book with artistic entries by important painters", which is now part of the Städtisches Museum's collection.
[2] In September 1924, Ralfs founded the Society of Friends of Young Art (Gesellschaft der Freunde junger Kunst - GFJK) and became its first chairman.
[11] After Adolf Hitler came to power in 1933, the Society of Friends of Young Art (GFJK) was forced by Nazi pressure to dissolve.
After Otto Ralfs died in an accident in 1955, his wife survived him by almost 40 years – in 1991, she was awarded the City of Braunschweig's Citizens' Medal for the couple's special services to the "promotion of fine art" and a play was written about the family's history.