The Kodiak bear (Ursus arctos middendorffi), also known as the Kodiak brown bear, sometimes the Alaskan brown bear, inhabits the islands of the Kodiak Archipelago in southwest Alaska. It is the largest recognized subspecies or population of the brown bear, and one of the two largest bears alive today, the other being the polar bear. They are also considered by some to be a population of grizzly bears.

Physiologically and physically, the Kodiak bear is very similar to the other brown bear subspecies, such as the mainland grizzly bear (Ursus arctos horribilis) and the extinct California grizzly bear (U. a. californicus), with the main difference being size. While there is generally much variation in size between brown bears in different areas, most usually weigh between 115 and 360 kg (254 and 794 lb). The Kodiak bear, on the other hand, commonly reaches sizes of 300 to 600 kg (660 to 1,320 lb), and has even been known to exceed a weight of 680 kg (1,500 lb). Despite this large variation in size, the diet and lifestyle of the Kodiak bear do not differ greatly from those of other brown bears.

Kodiak bears have interacted with humans for centuries, especially hunters and other people in the rural coastal regions of the archipelago. The bears are hunted for sport and are encountered by hunters pursuing other species. Less frequently, Kodiak bears are killed by people whose property (such as livestock) or person are threatened. There is increasing focus on conservation and protection of the Kodiak bear population as human activity in its range increases. The IUCN classifies the brown bear (Ursus arctos), of which the Kodiak is a subspecies, as being of "least concern" in terms of endangerment or extinction, though the IUCN does not differentiate between subspecies and thus does not provide a conservation status for the Kodiak population. The Alaska Department of Fish and Game however, along with the United States Fish and Wildlife Service to a lesser extent, closely monitor the size and health of the population and the number of bears hunted in the state.