Ossobuco or osso buco (pronounced [ˌɔssoˈbuːko]; Milanese: òss bus or òs büüs [ˌɔz ˈbyːs]) is a specialty of Lombard cuisine of cross-cut veal shanks braised with vegetables, white wine, and broth. It is often garnished with gremolata and traditionally served with either risotto alla milanese or polenta, depending on the regional variation. The marrow in the hole in the bone, a prized delicacy, is the defining feature of the dish.

The two types of ossobuco are a modern version that has tomatoes and the original version which does not. The older version, ossobuco in bianco, is flavoured with cinnamon, bay leaf, and gremolata. The modern and more popular recipe includes tomatoes, carrots, celery, and onions; gremolata is optional. While veal is the traditional meat used for ossobuco, dishes with other meats such as pork have been called ossobuco.