Papaver setigerum reaches on average 20–80 centimetres (7.9–31.5 in) in height. The stem is erect and the leaves are simple, oblong, the lower ones are sessile, deeply lobed and toothed, the higher ones shortly pedunculated. The flowers at the apex of the stem are hermaphroditic, actinomorphic ("star shaped", "radial"), 4 to 10 cm in diameter. The corolla forms a cup with four pink-purple petals, with a dark purple blotch at the base. It has several stamens with dark filaments holding yellow anthers. Flowering occurs from May through June. The fruits are glabrous capsules 2 to 3 cm long, dehiscent along the holes located under the apical disc. The kidney-shaped seeds are about 1 mm wide.