Rumex alpinus, common name monk's-rhubarb,[1] Munk's rhubarb[2] or Alpine dock, is a leafy perennial herb in the family Polygonaceae.

The leaves are very large, ovate-round, with long stout leaf stalks and irregular margins.

The outer ones are recurved and the inner ones form fruit valves, which are roundly, wider than long, with cordate bases and entire margins.

This species prefers high-altitude environments rich in nitrates, at elevation of up to 2,000 to 2,400 metres (6,600 to 7,900 ft) above sea level.

It can be found in arable land, fields, yards, rubbish dumps, roadsides and shores.