The W Budapest will open in 2020 in the 19th-century Drechsler Palace, which formerly served as the longtime home of the Hungarian Ballet Academy.
The building, which has been empty for more than a decade, will be renovated to include 162 rooms, a restaurant, a bar, and three meetings spaces.
The property, owned by Qatar's Constellation Hotels Holding Ltd., is located on Andrassy Avenue, known as "Budapest's Champs-Elysees." The hotel will be the first W-branded hotel in Hungary.
Built in the 1890s, the building is located across the street from the Hungarian State Opera House and has at times housed apartments and a cafe in addition to the Ballet Academy.
Marriott acquired former W parent Starwood Hotels & Resorts last year.