Agusan may refer to the following:
In geography
Agusan (province), a former province in the Philippines, now divided between: Agusan del Norte Agusan del Sur Legislative district of Agusan in the Philippines for the former province before it was divided into two separate ones Agusan's at-large congressional district Agusan River, a river in Mindanao The Agusan Marsh Wildlife Sanctuary
Other
A symbol in the Tironian notes shorthand system () when used as an abbreviation for agus ("and") in Irish and Scottish Gaelic Agusan language, a Manobo language of The Philippines