More than 500 neo-Nazis had attempted to march to the site of the former prison in Berlin's western district of Spandau where Hess died in 1987, but were blocked by left-wing groups and local residents.
Police said today that 35 of those detained belonged to the far-right march, while four were taking part in the counter-protest.
Twelve of the far-right protesters are being investigated for displaying forbidden symbols.
Others detained are being investigated for breach of the piece, assault, resisting arrest, drug offenses and breaking the law on public assembly.