Dipterocarpus dyeri (Khmer: rôyiëng, chhë tiël pruhs, chhë tiël th'nô:r, local name Kompong Thom: chhieutiel chgor, name used for commercial timber and the group of trees harvested for such: keruing, Vietnamese: dau song nang, is a species of tree in the family Dipterocarpaceae found in Myanmar, Thailand, Peninsular Malaysia (Kedah, Perlis), Cambodia and Vietnam. The tree is found in lowland semi-evergreen dipterocarp forests and Schima/bamboo forests, an alternative habitat description is mixed dense forests of the plains, mainly among rivers and valleys. The tree is a climax or late successional species, which in some secondary forests forms relatively young pure colonies. The conservation status is based on rates of habitat loss, the major threat to the taxa, though in Vietnam it is cit