Carex ulobasis, also known as montane sedge, is a tussock-forming species of perennial sedge in the family Cyperaceae. It is native to parts of eastern Russia in the north to Korea in the south.
The sedge has a short and woody rhizome with densely tufted red-brown coloured culms that are in height. The culms are triangular in cross section with a smooth lower portion but with a rougher texture toward the ends. The culms are sheathed at the base but the sheaths will crumble into fibres over time.