Agaricus Bisporus, known as table mushroom, cultivated mushroom or button mushroom, is an edible basidiomycete fungus which naturally occurs in grasslands, fields and meadows across Europe and North America, though has spread much more widely and is one of the most widely cultivated mushrooms in the world. The original wild form bore a brownish cap and dark brown gills but more familiar is the current variant with a white form with white cap, stalk, flesh, and brown gills.

Some grocery stores in the western world sell this mushroom in canned and fresh preparations. An agaric, its gills are often left on in preparations. It can be found cooked on pizzas and casseroles, as stuffed mushrooms, raw on salads, and in various forms in a variety of dishes.

Agaricus bisporus is known by many names several of which refer to different stages; 'button mushroom' when sold, collected or eaten young, unopened form, 'Crimini mushroom' or ;baby bella'. It is known as the 'Champignon de Paris' in France. It is also often called simply 'Champignon' (the French word for 'fungus') in several languages. Agar mushrooms compromise 90% of Australia's mushroom cultivation.

The cultivated mushroom is a member of the large genus Agaricus, which has numerous members which are edible, tasty and collected worldwide.