From its inception, the Cooper Union Museum was dependent on the Hewitt sisters and their friends for donations. After Sarah Cooper-Hewitt's death in 1930, it was feared that public interest, especially that of sponsors, in a museum of decorative arts would decrease. In 1934, the Museum's Board of Directors and interested persons founded the Friends of the Museum of the Cooper Union. In addition to collecting dues from members, the Friends of the Museum solicited annually for funds, and, from 1936, met annually for tea parties and lectures. The funds collected were used to purchase objects for the Museum, to pay costs for extra personnel and maintenance, and to encourage the study of decorative arts.

In 1963 the Trustees of the Cooper Union planned to close the Museum for financial reasons, only to face serious protests from many in the art and museum world, led by Henry Francis DuPont. The Friends group seems to have been submerged in a new organization, the Committee to Save the Cooper Union Museum, and to have ended a separate existence at that time.