Árni M. Mathiesen (born 2 October 1958 in Reykjavík) is an Icelandic politician.

He studied fish pathology at the University of Stirling and in 1985 was awarded the MSc in Aquatic Veterinary Science.

[1] After completing his studies, he worked as veterinarian in various areas of Iceland, and served as veterinary officer for fish diseases 1985–1995.

He was chairman of the team handball division of his local FH club 1988–90 and was a member of the Flensborgarskóli school board from 1990 to 1999.

He is the ADG of the Fisheries and Aquaculture Department at FAO, in Rome, where he lives with his family, from 2010 to present.