Actinolite is a community on the Skootamatta River in eastern Ontario. Actinolite is in the Municipality of Tweed, in Hastings County, on Highway 37 just south of Highway 7 and north of Tweed. It is well known for the Log Cabin Restaurant; not for the cuisine, which is unremarkable, but as it is a major stopover point for coach bus runs between the Belleville and Ottawa areas.

When it was first founded in 1853, it was called Troy. A number of sawmills were built on the river here. In 1859, it became Bridgewater. In 1895, it was renamed Actinolite after the mineral actinolite that was being extracted from open-pit mines near the town.