The black-billed shrike-tyrant (Agriornis montanus) is a species of bird in the family Tyrannidae. It is found in Argentina, Bolivia, Chile, Colombia, Ecuador, Peru, and is a vagrant to the Falkland Islands. It is a large flycatcher at 23–25 cm (9–10 in) long. Its natural habitats are subtropical or tropical high-altitude shrubland, subtropical or tropical high-altitude grassland, and pastureland.