Diphasiastrum sitchense, the Sitka clubmoss, is a pteridophyte species native to northern North America and northeastern Asia.

Leaves are appressed, broadly lanceolate, up to 3.2 mm (0.13 inches) long.

[3] It is known from every province in Canada, plus the US States of Alaska, Oregon, Washington, Idaho, Montana, Maine, New Hampshire, Vermont, and New York.

[4][5] It is also found in Greenland, St. Pierre and Miquelon, Yukon, Japan, and the Kamchatka Peninsula of Asiatic Russia.

[2] It can be found in alpine meadows, open rocky barrens, and coniferous woodlands.