Stomachs from six adults and one 12-month old babirusa (Babyrousa babyrussa)were collected from zoological gardens. The babirusa stomach was larger than that of the domestic pig (Sus scrofa), and possessed a large diverticulum ventriculi. Its gastric glands were confined to a small, easily identifable unit at the end of the corpus ventriculi, and the connections between the different stomach parts were wide and unrestricted, with the exception of the well-defined connection between the diverticulum ventriculi and the fundus ventriculi. Microscopically, the structure of the cardiac, gastric and pyloric glands was similar to that of Sus scrofa. However, the muscus-producing cardiac glands of babirusa occupied a larger area within the stomach (>70% versus 33%). The pH in the lumen of the cardiac gland area lay between 5.3 and 6.4 and micro-organisms were found here. It was hypothesised that the babirussa is a non-ruminant foregut-fermenting frugivore/concentrate selector.