Andrew William Mellon was an American banker, industrialist, philanthropist, art collector and Secretary of the Treasury from March 4, 1921 until February 12, 1932.

In 1913, along with his brother, Richard B. Mellon, he established a memorial for his father, the Mellon Institute of Industrial Research, as a department of the University of Pittsburgh. Today the institute is a part of Carnegie Mellon University. Mellon also served as an alumni president and trustee of the University of Pittsburgh, and made several major donations to the school, including the land on which the Cathedral of Learning and Heinz Chapel were constructed. In total it is estimated that Mellon donated over $43 million to the University of Pittsburgh.

During his retirement years, as he had done in earlier years, Mellon was an active philanthropist, and gave generously of his private fortune to support art and research causes. In 1937, he donated his substantial art collection, plus $10 million for construction, to establish the National Gallery of Art on the National Mall in Washington, D.C. The Gallery was authorized in 1937 by Congress.

Andrew Mellon was made a Freemason in 1928, and Raised in 1931.