Walther Forstmann (9 March 1883 – 2 November 1973) was one of the most highly decorated U-boat commanders in the Kaiserliche Marine during World War I.

In his time as commander of U-12 and U-39 in World War I, he conducted 47 patrols and succeeded in sinking 148 ships for a total tonnage of 390,797 gross register tons (GRT).

Forstmann wrote his memoirs after the war in the book Hunting in the Mediterranean (German: Auf Jagd im Mittelmeer).

1951 - 1955 He became one of the advisors of the housing company - Rheini dwellings A.G. in Duisburg which was responsible for the movement of several villages to enable development of open cast coal mining.

In 1956 he was involved in the design structure of the 30 Pestalozzi villages (de) and became vice-president of the German settler federation, chairman of the executive committee of youth centre place work e. V. In 1968 he received an honorary Doctorate from the Roman Accademia Tiberina and in 1972 another from the university of the Mediterranean in Rome.