Marie Willem Frederik Treub (30 November 1858, Voorschoten – 24 July 1931, The Hague) was a Dutch politician.
Together with his two brothers Hector and Melchior, he enjoyed primary education in Voorschoten and attended the Gemeentelijke HBS in Leiden, from which he graduated in 1876.
in 1885, Treub became a professor teaching tax law in Amsterdam, and he became an editor of the Weekblad voor Notarisambt en Registratie and the Sociaal Weekblad en Vragen des Tijds, notarial weeklies with a progressive liberal leaning, two years later.
His political interest made him join the local classical liberal electoral association Burgerplicht, but it became apparent that its course could not be altered, and Willem Treub, along with others, established the radical electoral association Amsterdam.
Treub was elected into the municipal council of Amsterdam in 1889, and became the city's alderman of finance in 1893.