After the Second World War the Biennale resumed activity with one of its favourite subjects: French Impressionism, presented by Roberto Longhi in a memorable retrospective. The 24th Biennale in 1948 was particularly significant due to its reconsideration of the avant-garde, made possible also by the commitment of the foreign pavilions. The General Secretary Rodolfo Pallucchini organised the first five Biennale exhibitions after the War (from 1948 to 1956). This period of time enabled him to present an overall view of European avant-garde, which still however, excluded Dadaism. Above all, he succeeded in rendering contemporary art more accessible to the Italian public.
The two major events of 1948 were Picasso's retrospective exhibition (first appearing in the Biennale at the age of 67, presented by Guttuso), and the exhibition of the Peggy Guggenheim collection featuring 136 works by 73 artists, presented by Giulio Carlo Argan. In following years more avant-garde retrospectives were presented. At this time the importance of the avant-garde movement was fully recognised: prizes were awarded to Braque (1948), Matisse (1950), Dufy (1952), Ernst, and Arp (1954). The 1950 edition was also a success, featuring four significant exhibitions on Fauves, Cubism, and Futurism, and the Der Blaue Reiter movement. The astonishing pictorial violence of the Mexican Pavilion was a revelation; featuring the "four greats": Jose Clemente Orozco, Diego Riviera, David Alfaro Siqueiros, and Rufino Tamayo.
In 1952 Pallucchini proposed a comparative exhibition featuring Italian Divisionism (Previati, Pellizza da Volpedo, and Segantini) alongside French Pointillism (Pissarro, Signac, and Seurat). A major exhibition of Toulouse-Lautrec prints was set up in the Napoleonic Hall.
In the meantime new trends broke out. The American Pavilion presented Jackson Pollock's action painting. The special prize for sculpture was awarded to Calder in 1952, and Chadwick in 1956.
The Biennale of 1954 featured Surrealism. The works of Courbet, Munch, Klee, and Magritte were exhibited in their respective pavilions. Under the direction of the new General Secretary Gian Alberto Dell'Acqua, who was in charge from 1958 to 1968, the Biennale contributed significantly to the diffusion of contemporary art.