Aspalathus aciphylla is a robust, single-stemmed, sprawling or erect shrub reaching heights from 30 cm to 2 m. The branches are slightly hairy.
The three-foliolate leaves grow tufted, the leaves within each tuft often unequal in size. The hairless leaflets are linear to somewhat cylindrical and notably spine-tipped.
The yellow flowers grow solitary or in small groups at the tips of short, lateral branchlets. The pointed calyx lobes are pale, sometimes light brown. The hairless flowers are about 11 mm long. Flowering happens from before midwinter to early summer.
The species distribution is in the Western Cape from Caledon and Bredasdorp to the Eastern Cape as far as Humansdorp; also inland on the Little Karoo mountain ranges.
The habitat is fynbos mountain slopes and flats, mainly in sandstone derived soils. The species is not considered to be threatened in its habitat early in the twenty first century (Vlok and Schutte-Vlok, 2015; Bond and Goldblatt, 1984; iNaturalist; http://redlist.sanbi.org).