Strobilanthes flexicaulis is a species of flowering plant in the family Acanthaceae, native to the Ryukyus and Taiwan.

[1] A much-branched subshrub reaching 1 m (3 ft), it is found at elevations from 200 to 2,300 m (700 to 7,500 ft), typically beside streams in forests.

[2] The following varieties are accepted:[1] All Strobilanthes flexicaulis var.

flexicaulis individuals simultaneously flower at six-year intervals, and then die, but S. f. var.

tashiroi does not exhibit periodic mass flowering.