The Blairmore Group, originally named the Blairmore Formation, is a geologic unit of Early Cretaceous age in the Western Canada Sedimentary Basin that is present in southwestern Alberta and southeastern British Columbia. It is subdivided into four formations: Cadomin Formation, Gladstone, Beaver Mines and Ma Butte, all of which are defined by type sections, most of which contain plant fossils. In some areas the Blairmore contains significant reservoirs of natural gas.

The Blairmore group includes the conglomerate and quartzose sandstones of the Cadomin Formation at the base, and grades to sandstone, siltstone, mudstone, and limestone in the overlying formations.

The Cadomin Formation has beds of quartzose sandstone and, in some sections, especially in the eastern foothills, is totally quartzose sandstone. It is normally a very durable, siliceous pebble conglomerate. A sequence of interbedded, highly variable-proportioned grey mudstone to sandstone layers makes up the bottom portion of the underlying Gladstone Formation. Sandstones, whose grain size rarely exceeds fine, frequently show a noticeable upward decline in grain size. Dark grey, argillaceous limestone and fossiliferous calcareous shale make up the top Gladstone Formation. Limestone deposits are few or nonexistent north of the Clearwater River (52°N).

Both the Beaver Mines Formation in the south and the Mountain Park Formation in the north are made up of interbedded mudstone to very fine-grained sandstone with minor but noticeable thicker and coarser sandstone units that have abrupt bases and fining upward grain size. Conglomerate beds make up a small portion. The marine mudstone Moosebar Member of the Malcolm Creek Formation, which is restricted to the region north of Waiparous Creek (51°20'N), is overlain by the notable sandstone-dominated Torrens Member and the coal-bearing Grande Cache Member. Mudstone to very fine-grained sandstone, as well as layers of conglomerate and coarser sandstone, make up the Ma Butte Formation.

The Beaver Mines and Ma Butte formations in the upper part of the group also include minor beds of bentonite and tuff.

In the type area, tuffaceous mudstones are widespread in the top portion of the formation, but they vanish to the northwest along the foothills. North of the Clearwater River, the structure is completely missing. Various shades of red and green, frequently speckled south of the Bow River, are particularly prevalent. Except in the Mountain Park Formation, where greenish grey predominates in more southerly areas and is increasingly prominent higher, grey prevails to the north. In the Smoky River region, the uppermost part of the formation, the proportion of the section with a conspicuously greenish tint is restricted to a subtle shade of greenish-grey as it declines northward.

The Blairmore Group is subdivided into the following formations from top to base:

Some early workers included the Crowsnest Formation, which overlies the Ma Butte Formation, at the top of the Blairmore Group, but that practice has been abandoned.