Shrubs or small trees, 5–8 m tall; older branches smooth, glabrous; young shoots grayish tomentose, glabrescent. Petiole terete, 25–30 mm, tomentose, glabrescent; leaf blade thick, leathery, oblong-elliptic, oblong-obovate or broadly lanceolate, broadest above middle of blade, 11–22 × 5–7 cm; base broadly cuneate or rounded; apex obtuse; abaxial surface with dense, brown, 2-layered, indumentum, upper layer of narrowly cup-shaped strongly fimbriate hairs, lower layer whitish and compacted; adaxial surface deep green, glabrous, midrib plane adaxially; lateral veins 18–19-paired, impressed adaxially. Inflorescence ca. 15-flowered; rachis pubescent. Pedicel 3–3.5 cm, sparsely tomentose; calyx teeth 7, ca. 1 mm; corolla campanulate, pale rose, with a crimson basal blotch, ca. 3 cm, lobes 7, suborbicular, ca. 1 cm; stamens 14, 1–2.2 cm, filaments pubescent at base; ovary conoid, 5–6 × 2–3 mm, glabrous; style slender, 3–3.5 cm, glabrous. Capsule not known. Fl. May–Jun.

Rhododendron peregrinum Tagg (Notes Roy. Bot. Gard. Edinburgh 16: 202. 1931), which is unknown in the wild, is almost certainly a hybrid of R. galactinum.

Thickets, mountain slopes, stream banks; 2900–3500 m. W Sichuan.