Arne Wilhelm Kaurin Tiselius (Stockholm 10 August 1902–Uppsala 29 October 1971), Swedish biochemist.

He became research assistant in The Svedberg's laboratory in 1925 and obtained his doctor's degree in 1930 on the moving-boundary method of studying the electrophoresis of proteins.
From then to 1935 he published a number of papers on diffusion and adsorption in naturally occurring base-exchanging zeolites, and these studies were continued during a year's visit to H.S. Taylor's laboratory in Princeton with support of a Rockefeller Foundation Fellowship.
On his return to Uppsala he resumed his interest in proteins, and the application of physical methods to biochemical problems. This lead to a much improved method of electrophoretic analysis which he improved in subsequent years.
Tiselius took an active part in the reorganization of scientific research in Sweden in the years following World War II, and was President of the International Union of Pure and Applied Chemistry 1951-1955.
He died 29 October 1971 in Uppsala.