The chestnut-headed partridge (Arborophila cambodiana) is a bird species in the family Phasianidae. It is found in highland forest in Cambodia, specifically the Cardamom Mountains. The Siamese partridge, subspecies A. c. diversa, has sometimes been considered as a separate species..
The chestnut-headed partridge was formally described in 1928 by the French ornithologists Jean Théodore Delacour and Pierre Jabouille based on a specimen collected near Bokor in southern Cambodia. They placed the new species with the partridges in the genus Arborophila and coined the binomial name Arborophila cambodiana.
Three subspecies are recognised:
The subspecies A. c. diversa has sometimes been considered as a separate species, the Siamese partridge.