The Armadillo Formation is a stratigraphic unit of Miocene age in northwestern British Columbia, Canada.

The Armadillo Formation takes its name from Armadillo Peak, a volcanic peak east of Raspberry Pass in the middle of the Mount Edziza volcanic complex.

[1] The Armadillo Formation consists of volcanic rocks of both felsic and mafic compositions.

They are the products of a long period of bimodal volcanism, having issued from multiple eruptive centres.

Basalt is the main mafic rock of the Armadillo Formation and forms lava flows.