Allium obtusum is a species of wild onion known by the common name red Sierra onion or subalpine onion. It is native to eastern California and western Nevada. It is a common member in the granite foothills and mountains of the Sierra Nevada and southern Cascade Range, from Tulare County to Siskiyou County, from elevations 0f 800–3,500 metres (2,600–11,500 ft). In Nevada, it is reported only from Washoe County in the northwestern part of the state.