The brown-winged whistling thrush (Myophonus castaneus), also known as the Sumatran whistling thrush or chestnut-winged whistling thrush, is a passerine bird belonging to the whistling thrush genus Myophonus in the family Muscicapidae. It is endemic to the island of Sumatra in Indonesia. In the past, it has often been lumped together with the Javan whistling thrush (M. glaucinus) and Bornean whistling thrush (M. borneensis) as the "Sunda whistling thrush" (M. glaucinus) but it is now often regarded as a separate species based on differences in plumage and measurements.