Yes, pure, 100% ground almond flour is gluten-free. Almond flour, sometimes called almond meal, is made from finely-ground almonds (with or without their skins), which are naturally gluten-free.
Flour made with skin-on almonds will have a darker color and is suitable for rustic breads or baked goods that also have a dark color, such as chocolate desserts or gingerbread. Almond flour without the skin is made from blanched almonds and has a light ivory color. It can be used in light-colored cakes and muffins.
Using this flour adds a delicate almond flavor and gives structure to baked goods. You can make your own by pulsing whole raw almonds or whole blanched almonds in a food processor. You can store almond flour in the freezer for up to six months.
As always, read the ingredient list before purchasing a product. Many manufacturers mix many different flours together to achieve an optimal flour blend. Ensure no wheat, rye or barley has been added to the almond flour.