The digestive capabilities of the Cape porcupine (Hystrix africaeaustralis) were studied using captive and field animals. The stomach contents comprised 6,47% of the body mass and had a low pH (2,0).The Cape porcupine also has a long small intestine (670 cm). The large stomach and small intestine form a very efficient protein digesting (83,8%) apparatus. The caecum is relatively small, constituting 2,7% of the body mass. On a high fibre diet food intake declined and retention time of digesta in the tract increased. Fibre is probably only included in the diet at times of food shortage.