Abstract: Polygonum shuense and P.chayuum, two new species of Polygonum from China, are described. P.shuense is similar to P.subscapsum, but differs by the radical leaves crenate at margins, and altenuate and decurrent at base, flowers white, styles 3 and free, and achenes long ovate and opaque. P.chayuum is distributed in Xizang, with stem unbranched, leaves on the upper part of stem, and only ochreas on the lower part of the stem. Such characters are unique in Polyonum and differ apparently from those of other species.

Key words: Polygonum, new species, Polygonum shuense A.J.Li et B.J.Bao, Polygonum chayuum A.J.Li et B.J.Bao, China