Of the 477 food items identified in the diet of the Australasian Harrier (Circus approximans), mammals (46%) were the main food. Birds and their eggs (41%) were the next most numerous food, and insects (8%) and fish and frogs (5%) were in about equal numbers. Live prey was numerically more important than carrion in all seasons and especially during summer. However, the biomass of carrion eaten annually was greater than that of live prey. Food items were taken according to their availability, and not according to preferences of the predator. The legal protection of the Australasian Harrier in New Zealand is recommended.