Paul Fillunger (June 25, 1883 in Vienna – March 7, 1937 in Vienna) was an Austrian geotechnical engineer.
Raised in a family of engineers, he studied at the Technische Hochschule in Vienna and took a position in the state-owned railway company in 1906. In 1908 he completed a PhD and then went to teach mathematics, machine industry and then mechanics at the University of Vienna.