The National Gallery houses the richest and most complete collection of works of Bulgarian art created in the 20th century—some 30,000 museum artefacts. The beginnings were laid with the first state acquisitions at the Pavilion of Fine Arts of the First Plovdiv Expo (1892), and continued with the development of the Art Department of the National Museum. Its collections of about 1,250 works—painting, sculpture, graphics, and particular examples of the applied arts by Bulgarian and foreign artists—were transferred in 1948 to the National Gallery, then newly established as an independent institution.

The pictorial collection has been systematically enriched mainly through purchases from collective and individual exhibitions. Over the years, many donations by citizens have also been received, while the artists Vera Nedkova, Nikola Tanev, and Alexander Bozhinov left to the National Gallery their entire creative heritage as preserved in their ateliers. Donations by contemporary artists are extremely valuable; thanks to them, the tableau of the newest Bulgarian painting is being enhanced. In the 20th century, different ideas and artistic tendencies were intertwined in Bulgarian art; every decade possessed its own features, based on what had previously been accomplished and on brave experiments.

The graphic collection comprises pencil and ink drawings, watercolours and pastels, etchings and aquatints, wood engravings, dry needle and mixed media. Its variety of genres is also rich: landscapes and portraits, figural and abstract compositions, historical compositions, illustrations and caricatures. The collection makes it possible to both outline the individuality of the artists, as well as to track the pace and peculiarities, the technical growth and enrichment of the meaningful layers of Bulgarian graphic art.

Owing to the historical peculiarities of national development, the emergence of sculpture in Bulgaria took place only after the Liberation (1878). In the 20th century, generations of carvers won recognition, whose oeuvre was not only a testimony of the mastering of European tradition, but also a convincing example of weaving into it specific national stylistic features. The art of Bulgarian sculptors attracted attention with its high professionalism. Each generation made its way into artistic life and established a new aesthetics and poetics that permeated the entire process of creation of the works—from the choice of material, through preferences of genre, to the particular attitude towards the portrait image or the monumental work.

The collection of works of the decorative arts is unique in the country in its comprehensiveness. It includes ceramics, woodcarving, artistic fabrics, applied graphics and posters, ornaments, glass works, and scenographic designs. Many of their artists began their creative development in the 1960s, established contemporary forms of decorative art, and prepared the younger generations that were successfully making their marks on the artistic scene in Bulgaria and around the world.