Flowering stem 20–40 cm long. Rhizome long creeping, 1–3 mm in diameter. Leaves basal and cauline, trifoliolate, 5-foliolate, sometimes 7-foliolate; leaflets ovate, 2.5–4 × 2–3 cm, apex acuminate, base deeply cordate with regularly rounded lobes, terminal leaflet with equal rounded lobes, lateral leaflets oblique with outer lobe large and rounded, inner lobe smaller and rounded, margin spinose-serrate, abaxially long-pilose. Flowering stem usually with two alternate or opposite trifoliolate leaves, or sometimes three alternate trifoliolate leaves, occasionally two opposite 5-foliolate leaves, rarely three or four whorled leaves with unifoliolate, trifoliolate and/or 5-foliolate. Inflorescence raceme, 7–14-flowered, 10–16 cm long, glandular hairs. Flowers ca. 10 mm in diam., yellow, pedicels 1–2 cm long, glandular hairy. Outer sepals 4, pale purple, broadly ovate, ca. 4 × 1.5 mm. Inner sepals 4, purple-red, elliptic, ca. 5 × 1.5 mm. Petals 4, yellow, or sometimes purple-red spotted at base, spurless, ca. 6–8 × 4–5 mm, obovate, apex subacute. Stamens ca. 4.5 mm; anthers yellow, ca. 1.5 mm.

Epimedium ecalcaratum occurs in Baoxing, Luding, Shimian and Pengxian, Sichuan, often on mountain slopes and grassland with elevations ranging from 1100 m to 2100 m.

Epimedium ecalcaratum flowers from April to May, and fruits from May to August.

Epimedium ecalcaratum was designated as endangered (EN) according to the International Union for Conservation of Nature (IUCN) Red List criteria (IUCN 2015), because of exploitation for medicinal use.

China. Sichuan: Baoxing, B.L. Guo 0539 (IMD), D.J. Yu 1892 (PE), G.Y. Zhong Z-8901 (SM), Y.Q. Xu & S.X. Liu 2015019 (JXCM), 2016022 (JXCM). Luding, B.L. Guo 0611 (IMD). Shimian, Shimian Econ. Pl. Exped. 78-0222 (SM). Pengxian, Z.B. Feng, D.H. Zhu & X.J. Li, 20070428 (HX).