The museum collection consists of Art Nouveau objects manufactured or used in Riga and in the territory of Latvia in the early 20th century. Among the collected object there are furniture, items of interior design and applied arts, clothing and accessories, works of art, household items, photographs, documents, printed materials, memorabilia related to life and work of Konstantīns Pēkšēns etc.

The museum preserves and promotes the Art Nouveau heritage not only by exhibiting it in the Art Nouveau apartment, but also by organising various exhibitions in Latvia and abroad every year, holding educational events for different target audiences and carrying out research on the items of the Art Nouveau period.

The first items appeared in the museum collection in 2008 under the guidance of Agrita Tipāne. Architect Eižens Upmanis, art historians Ojārs Spārītis, Ilona Audere, Daiga Upeniece and Vita Banga took an active part in this work. As two world wars had ravaged Latvia in the 20th century, the antiques market in Latvia was minuscule and the number of items preserved was very small. Besides, many works of art and other objects were destroyed in the post-war period. Items were selected from a small supply of antique shops and donations of individuals. The creation of the Art Nouveau collection received wide public acclaim.

At the opening ceremony of the museum in 2009, an appeal was made to the inhabitants of Riga to donate items related to their family history to the museum. This tradition continues still today, donated items tell about the past and they have often been family relics. At present the museum collection contains more than 7000 objects and it is the largest Art Nouveau collection in the Baltic States.