Philipp Forchheimer (7 August 1852 in Vienna – 2 October 1933 in Dürnstein, Lower Austria) was an Austrian engineer, a pioneer in the field of civil engineering and practical hydraulics.
He was professor in Istanbul, Aachen and Graz.
He introduced mathematical methodology to the study of hydraulics, thus establishing a scientific basis for the field.
He was director of the Graz University of Technology until 1897.
In addition to his teaching, he worked as a consultant for construction projects.
He made proposals for the construction of a tunnel under the English Channel.