Herbs, perennial, 20-50 cm tall, sometimes caespitose; rhizomes slender. Stems erect, simple, striate, glabrate, densely minutely reddish stipitate glandular, leafy. Leaves basal and cauline; cauline leaves reduced upward, thin, abaxially pale green, glabrous, eglandular, adaxially scabrous distally, margin sparsely serrulate, scabrous-ciliate, midvein prominent, apex acuminate, tip rounded; basal leaves withered or present at anthesis, sessile or shortly petiolate, oblanceolate, 3-14.5 × 0.4-1.5 cm; middle cauline leaves sessile, lanceolate, 2.5-6 × 0.4-0.9 cm, base rounded-auriculate, subclasping; upper leaves linear, acute. Capitula terminal, 4-6 in lax corymbiform synflorescence, 2-4 cm in diam.; peduncles 1.5-13 cm; bracts linear, densely minutely stipitate glandular. Involucres 8-9 mm; phyllaries 3-seriate, subequal, membranous, apex acute to acuminate, reddish purple; outer phyllaries lanceolate, ca. 6 × 1.5-2 mm, abaxially densely minutely stipitate glandular; inner phyllaries linear-lanceolate, ca. 7 × 0.9 mm, minutely stipitate glandular distally, margin scarious, erose, purplish distally, ciliate distally. Ray florets 25-40, bluish mauve to purple, tube distally hairy and minutely stipitate glandular, lamina 10-12 × ca. 1.5 mm; disk florets yellow, ca. 6 mm, tube ca. 2 mm, limb funnelform, 4-4.5 mm, proximally hairy, lobes erect, triangular, 0.7-0.8 mm. Achenes narrowly obovoid, 3-4 mm, sparsely to moderately strigillose, minutely stipitate glandular distally, margin 6-ribbed. Pappus 4-seriate, white; outermost series of scales linear, 0.7-1 mm; bristles barbellate; outer bristles few, slender, 2-2.5 mm; inner bristles 5-5.5 mm, acute; innermost bristles 5.7-6 mm, weakly clavate. Fl. Aug-Sep.
Mountain forests or streamsides, disturbed damp shrublands; 3100-3500 m. NC Sichuan (Barkam, Lixian).
Aster setchuenensis is distinguished by its scabrous leaves and capitula in lax corymbiform synflorescences.