The Rambutan fruit is a round to oval single-seeded berry, 3–6 cm (rarely to 8 cm) long and 3–4 cm broad, borne in a loose pendant cluster of 10–20 together. The leathery skin is reddish (rarely orange or yellow), and covered with fleshy pliable spines, hence the name, which means 'hairs'. The fruit flesh, which is actually the aril, is translucent, whitish or very pale pink, with a sweet, mildly acidic flavor very reminiscent of grapes.

The single seed is glossy brown, 1–1.3 cm, with a white basal scar. Soft and containing equal portions of saturated and unsaturated fats, the seeds may be cooked and eaten. The peeled fruits can be cooked and eaten: first, the grape-like fleshy aril, then the nutty seed, with no waste.