The holdings of the new Museu del Modernisme de Barcelona come from the private collection that two Barcelona antique dealers, Fernando Pinós and María Guirao, have amassed during their 40 years in the business. The museum is dedicated exclusively to Catalonia's home-grown art-nouveau movement, modernisme. The collection on shows consists of 350 works by 42 of the most representative modernista artists, including Joan Busquets, Ramón Casas, Antoni Gaudí, Gaspar Homar, Josep Llimona, Joaquim Mir and Puig i Cadafalch, in their different disciplines: painting, sculpture, furniture and the decorative arts.

The Museu de Modernisme de Barcelona is housed in a centrally located modernista building designed by the architect Enric Sagnier. The Catalan vaults were restored and the original flooring on the ground floor preserved as part of the refurbishment project to house the museum. It has a floor space of 1,000m2. The top floor of the Museu showcases the furniture and decorative arts and has a room dedicated to Antoni Gaudi. The ground floor displays paintings, sculptures and stained glass.