Asterolasia rivularis is a small, upright shrub, with narrow leaves and yellow flowers.

Asterolasia rivularis is a small shrub to 1.5 m (4 ft 11 in) high with young branches covered in brown to grey star-shaped, short matted hairs.

The leaves may be narrowly oblong, narrow-oblong to wedge shaped and tapering at the base, 1–2.5 cm (0.39–0.98 in) long, 2–3 mm (0.079–0.118 in) wide.

The flowers are either borne from leaf axils or at the end of branches in small clusters of 1-3, yellow petals about 6 mm (0.24 in) long, upper surface with rusty star-shaped to short matted hairs.

[1][4] Asterolasia rivularis has a restricted distribution, it is found growing along streams near Buxton.