Karl Grobben (August 27, 1854, Brno – April 13, 1945, Salzburg) was an Austrian biologist.
He graduated from, and later worked at, the University of Vienna, chiefly on molluscs and crustaceans.
He was also the editor of a new edition of Carl Friedrich Wilhelm Claus' Lehrbuch der Zoologie, and the coiner of the terms protostome and deuterostome.