Walther Penck (30 August 1888 – 29 September 1923) was an Austrian geographer, born in Vienna as son of geographer Albrecht Penck.
Walther Penck worked 1912-1914 in Argentina as a geographer, and is best known for his contributions to the field of geomorphology. In particular he opposed key elements of the Davisian cycle of erosion, concluding that the process of uplift and denudation occur simultaneously, at a gradual and continuous rate. His book, Morphological Analysis of Landforms, was published posthumously in 1924 by his father.
He died in Stuttgart, Germany.