Sigmund Hågvar (born 2 September 1944) is a Norwegian entomologist and environmentalist.
He finished his secondary education at Valler in 1963.
He became a professor of nature conservation at the Norwegian University of Life Sciences.
Hågvar chaired the Norwegian Entomological Society from 1991 to 1995.
In 2006 he became a fellow of the Royal Swedish Academy of Agriculture and Forestry.
He has also had insects named after him, namely Syntemna haagvari and Vertagopus haagvari.
He resides at Nordstrand.