Plants annual, 50-80 cm tall. Stem erect, robust, branched in upper part, sparsely glandular hairy or glabrous. Leaves alternate; petiole 2-5 cm; leaf blade ovate-oblong or ovate-lanceolate, 7-18 × 2.5-5 cm, lateral veins 6-8 pairs, base cuneate, margin coarsely crenate or crenulate, apex acuminate. Inflorescences axillary; racemose, 5-13-flowered; peduncles 6-10 cm. Pedicels slender, bracteate at base; bracts ovate, apex glandular-aristate. Flowers yellow. Lateral sepals 2, broadly ovate, apex glandular-aristate. Lower sepal funnelform, narrowed into a curved, long spur. Upper petal orbicular, apex mucronulate, abaxial midvein carinate; lateral united petals ± clawed, 2-lobed; basal lobes suborbicular; distal lobes narrowly lanceolate. Anthers obtuse. Capsule linear. Fl. Aug-Sep.

The whole plant is used medicinally for relaxing and activating the tendons and for treating injuries, trauma, and snakebites.

This species is closely related to Impatiens pinetorum J. D. Hooker ex W. W. Smith, which was (?erroneously) recorded from W Yunnan (Tengchong) in FRPS (47(2): 60-61. 2001). According to the protologue and a photograph of the type specimen, the bracts of that species are ovate, small, glandular aristate, and the lateral sepals apically shortly aristate. It seems to be similar to I. loulanensis but differs in having flowers smaller, ca. 2 cm, yellowish, red spotted, and lower sepal funnelform with a slender, erect spur longer than limb.

● Forest understories, moist places in valleys, grasslands, along canals; 700-2500 m. Guizhou, Yunnan.