Upon release from prison, Peiper worked for the Porsche and Volkswagen automobile companies and later moved to France, where he worked as a freelance translator. Throughout his post-war life, Peiper was very active in the social network of ex-SS men centred upon the right-wing organisation HIAG (Mutual Aid Association of Former Members of the Waffen-SS).

In 1976, Peiper died from asphyxiation after communist arsonists discovered his identity and set his house on fire.