 In 1879, he became professor of political science at Aachen University of Technology, but moved quickly to Universität Rostock, 1884 at the University of Marburg and 1897 to the Technical University of Charlottenburg.Paasche developed a national statistical index (Paasche index) and analyzed the German sugar industry.In 1906, he gave up his professorship to devote his time to politics.