Sargocentron spiniferum is the largest squirrelfish in its range and can reach up to 51 cm (20 in) in length and 2.6 kg (5.7 lb) in weight (the Atlantic Holocentrus adscensionis can surpass the length, but it is slimmer).

It has silver scale margins, a spinous dorsal fin and a large deep red patch just behind the eyes.

It bears a very long preopercle spine (near the gill-opening).

This species is widespread throughout the tropical Indo-Pacific, from the Red Sea and Indian Ocean up to Hawaii, Japan and southern Australia.

This squirrelfish can be found in tropical waters on coral reefs, from shallow water to a depth of 120 m (390 ft).