In 1944 the Library returns to the Ciutadella as the Library of the Art Museums of Barcelona. It is now a specialised municipal library. From this period we should point out the important work of the then, and up to 1985, director of Art Museums, Joan Ainaud de Lasarte. In those years Joan Ainaud gave a great boost to acquisitions, which went from 8,000 to 80,000 pieces.

1944 The Library in the old Arsenal, home of the Museum of Modern Art, in the Ciutadella

The Library is on the first floor. View of the vestibule and the filing cabinet room. After the war, the unitary feel that the Museums of Barcelona had had until then was lost.

The Library changes its name to the Library of the Art Museums of Barcelona and is run by Barcelona City Council. The Library manager is, at this time, Aurora Díaz-Plaja.