Fallopia japonica (Houtt.) Ronse Decr. (Polygonaceae) is native to Amur, China North-Central, China South-Central, China Southeast, Hainan, Japan, Khabarovsk, Korea, Kuril Is., Manchuria, Nansei-shoto, Primorye, Sakhalin, Taiwan. Flora of the World documents 1 occurrence across 1 country.