Sir Arthur Harden (12 October 1865–17 June 1940) was an English biochemist. He shared the Nobel Prize in Chemistry in 1929 with Hans Karl August Simon von Euler-Chelpin for their investigations into the fermentation of sugar and fermentative enzymes.

He was educated at a private school and at Tettenhall College, Staffordshire, and entered Owens College in the University of Manchester in 1882, graduating in 1885.
In 1886 Harden was awarded the Dalton Scholarship in Chemistry and spent a year working with Otto Fischer at Erlangen.
In 1907 he was appointed Head of the Biochemical Department, a position which he held until his retirement in 1930.
Harden was knighted in 1926, and received several honorary doctorates.
A Fellow of the Royal Society, he received the Davy Medal in 1935.