Paul Joseph Guillaume Hillemacher (25 November 1852 – 13 August 1933)was a French composer and classical pianist.Born in Paris, Hillemacher studied at the Conservatoire de Paris in François Bazin's class. Second prize for harmony in 1870, first runaway in fugue two years later, he won, in 1873 a Second Prix de Rome then, in 1876, the Premier Grand Prix de Rome with his cantata Judith. He composed many stage music, operas, symphonies and melodies.
Most of his works were composed in collaboration with his brother Lucien Joseph Edouard Hillemacher (Paris, 10 June 1860 - Paris 2 June 1909).
Their first collaboration began in 1879 with two melodies, Le dernier banquet and Barcarolle and took its full measure in 1881, the date on which they signed their works, "P.L. Hillemacher", adopting the name Paul-Lucien Hillemacher.
In 1882 they published a collection of Twenty melodies as well as the symphonic poem Loreley which won the prize of the City of Paris. One of their melodies, Ici-bas, was published by mistake under the name Debussy, which testifies to their fame.
Lucien Hillemacher won a Second Prix de Rome in 1879 and the First Grand Prix de Rome in 1880 with his Scène lyrique Fingal after Charles Dancours. We know of him a piece for organ in "G" sharp minor (1907)
The two Hillemacher brothers were the sons of the academic painter Eugène Ernest Hillemacher.