Tetramolopium stemmermanniae is a perennial shrub that grows erect, reaching up to 1.5 meters tall. The plant is single-stemmed at the base and branches above. The stems are round, sparsely strigose, glandular, and resinous. The leaves are alternate, linear to lanceolate, measuring 3.6–7.3 cm long and 3.7–8.5 mm wide. The leaf surfaces are strigose and glandular-punctate, with more densely strigose midribs on the adaxial (upper) surface and even more densely strigose on the abaxial (lower) surface. The margins are strigose and subsessile. The flowers are arranged in open corymbose panicles with 38–71 heads. The peduncles are 0.5–1.6 cm long, flexuous, and covered with strigose hairs. Each flower head is subtended by two linear-lanceolate bracteoles, 1.5–2.0 mm long. The involucres are sub-hemispheric to obconic in shape, measuring 3.5–4.5 mm long and 1.0–1.5 mm in diameter. Phyllaries are 14–25 in 2–3 series, narrow, strigose near the base, and becoming sparsely strigose to glabrate toward the apex, with hyaline and ciliate margins near the base. Ray florets are pistillate, 15–25 in 1 series, with corolla tubes 1.7–2.1 mm long and ligules 1.3–2.0 mm long, usually white and becoming recurved with age. Disk florets are bisexual, 3–6 per head, goblet-shaped, with corollas 1.6–2.0 mm long, maroon in bud, and yellow in anthesis. The fruit is a simple, dry achene (cypsela), 1.5–2 mm long and 0.6–0.8 mm wide, oblanceolate, sparsely glandular strigose on both surfaces, becoming more strigose towards the apex. The edges are thickened and coriaceous, with 0–1 nerve on the faces. The pappus is white, 2.3–3.2 mm long, with barbellate bristles. It is found in native forests and old lava flows between 1525-1725 meters.