Max Mason studied at the University of Wisconsin where he received a B.Litt. in 1898 then went to Germany where studied for his doctorate at the University of Göttingen. His received his doctorate in 1903 for a dissertation entitled Randwertaufgaben bei gewöhnlichen Differentialgleichungen which had been supervised by Hilbert. Mason then returned to the United States, accepting a post of instructor in mathematics at Massachusetts Institute of Technology.
After spending 1903-4 at MIT, Mason spent the four years as assistant professor of mathematics at Yale. In 1908 he was appointed professor of mathematical physics at the University of Wisconsin. Mason remained at Wisconsin until 1925 but during World War I he worked as a member of the submarine committee of the NRC. During this period of war work he invented submarine detection devices.
Mason left Wisconsin in 1925 to become president of the University of Chicago. Then from 1928 he was the natural sciences director of the Rockefeller Foundation in New York. Between 1929 and 1936 he was president of the Rockefeller Foundation. He then became chairman of the team directing the construction of the Palomar Observatory which was completed in 1945.
Mason's research interests lay in differential equations, the calculus of variations and electromagnetic theory. He developed the relation between the algebra of matrices and integral equations as well as studying boundary value problems. Other topics in the large range of applied mathematics topics which he studied were existence theorems and asymptotic expansions. He also invented acoustical compensators.
He wrote a number of books, in particular The New Haven Mathematical Colloquium (1910) and he co-authored The Electromagnetic Field.
A strong supporter of the American Mathematical Society, he was an associate editor of the Transactions of the American Mathematical Society between 1911 and 1917. He was elected a member of the National Academy of Sciences.