Gruit (alternately grut or gruyt) is an old-fashionedherb mixture used for bittering and flavoring beer, popular before the extensive use of hops. Gruit or grut ale may also refer to the beverage produced using gruit.

Gruit was a combination of herbs, commonly including sweet gale (Myrica gale), mugwort (Artemisia vulgaris), yarrow (Achillea millefolium), ground ivy (Glechoma hederacea), horehound (Marrubium vulgare), and heather (Calluna vulgaris). Gruit varied somewhat, each gruit producer including different herbs to produce unique flavors and effects. Other adjunct herbs included black henbane, juniper berries, ginger, caraway seed,aniseed, nutmeg, cinnamon, and even hops in variable proportions. Some gruit ingredients are now known to have preservative qualities.