Pterostylis biseta, commonly known as the bristled rustyhood, is a plant in the orchid family Orchidaceae and is endemic to south-eastern Australia. It has a rosette of leaves at its base and up to seven relatively large, translucent flowers with green and brown marking with a brown to green insect-like labellum with bristly hairs. It occurs in New South Wales, South Australia and Victoria although in the latter state it has been separated into three species and is also under review in New South Wales.