[2][3] Melocactus neryi grows with dark blue-green to yellowish green, depressed spherical shoots that reach heights of growth of 5.5 to 18 centimeters (2.2 to 7.1 in) with a diameter of 7 to 20 cm (2.75 to 7.9 in).

The mostly single central spine is curved upwards and is 1 to 2.5 cm (0.4 to 1 in) long.

The up to 2.9 cm (1.14 in) long six to ten radial spines are curved.

The cephalium, which consists of fine, dense, reddish to slightly orange-red bristles, is up to 5 cm high and has a diameter of 4 to 9 cm (1.6 to 3.54 in).

The pink to lilac-pink fruits are 1–2 cm (0.4–0.8 in) long and sometimes flattened.