Field studies have provided an improved understanding of a known undescribed species of Tricoryne R.Br. and also shown that two or three separate species are included in an existing taxonomic concept. Two new species are described here, namely, T. tuberosa Keighery & T.D.Macfarl. and T. soullierae T.D.Macfarl. & Keighery. Tricoryne tuberosa has an extensive range in the northern wheatbelt and adjacent pastoral areas of south-western Western Australia. It has large root tubers, the leaves are withered at flowering time, and it forms clonal groups by long rhizomatous shoots. Tricoryne soullierae has a restricted distribution in remnant vegetation in the northern wheatbelt. It has fibrous roots and is conspicuously leafy when flowering.