Sir Norman Lethbridge Cowper, (15 September 1896 – 9 September 1987) was an Australian lawyer best known as the Senior Partner of the legal firm of Allen Allen & Hemsley which is now Allens.
Under Cowper's leadership, Allen Allen & Hemsley became one of Australia's leading law firms working for many of Australia's biggest corporations and expanded into Asia.
His most notable work as a lawyer was his involvement in the successful fight by 11 trading banks against the Chifley Government's bank nationalisation legislation.
He was knighted for his contribution to public affairs in 1967.
He also twice stood for Parliament as a candidate of the United Australia Party and was involved in drafting its constitution.
Cowper served on the boards of 20 Australian public companies including Borg Warner Australia and Angus & Robertson.