The following two new species of Acacia from the Koolanooka Hills, a low banded ironstone range in the northern wheatbelt region of south-west Western Australia (east of Morawa), are described: Acacia graciliformis Maslin & Buscumb and Acacia muriculata Maslin & Buscumb. Both are listed as Priority One species according to the Department of Environment and Conservation’s Conservation Codes for Western Australia Flora.