Tuber blackish brown, 1--2 cm, 3--6 mm in diam. Stem 1--5, 10--32 cm tall, 1--2 mm in diam, sparsely white hairy, branched. Basal leaves numerous, sheathed; petiole 3--12 cm; leaf blade ovate, suborbicular, or reniform, 1.2--3 cm, glabrous; leaflets flabellate-rhombic to obovate-rhombic, 0.6--2.5 × 1--2.8 cm, 3-parted; segments 2- or 3-lobed. Stem leaves shortly petiolate, similar to basal leaves but smaller. Bracts oblanceolate to obovate. Flowers 4--6 mm in diam. Pedicel slender, 1--2.5 cm, spreading white pubescent. Two new ent-kaurane-type diterpenoids, E-semiaquilegin (1) and Z-semiaquilegin (2), together with eight known compounds (3-10) were isolated from the dried roots of Semiaquilegia adoxoides (DC.) Makino. The structures of compounds 1 and 2 were elucidated mainly by 2D NMR techniques including 1H-1H COSY, HSQC, HMBC, NOESY as 16alpha-hydroxy-ent-kaurane-17,20-di-(3,4-dihydroxy-E-cinnamoyl) ester and its (Z)-isomer.