*School of Medicine, Belgrade, **Institute for Surgery Banjica, Belgrade ***University Clinical Centre of Serbia, Belgrade, *****Faculty of veterinary medicine, Belgrade

The investigation was carried out on 55 monkey (Cercopithecus aethiops) hearts by stereomicroscopic dissection and measurements. Latex injected specimens and corrosion cast showed that, like in humans, the RCA orifice was usually situated in the middle part of the right aortic sinus, slightly above the free edge of the valve leaflet (82.3%). The long RCA type was the most frequent finding (70.9%), as in humans. Among them, in 7.2 % RCA extends its route via the coronary groove, and terminats as the posterior left ventricular branch. In 23.6% RCA terminated as posterior right ventricular branch (short type), and occasionally, in 5.5 % RCA terminated as right marginal branch (extremely short type). The first branch of RCA very often was the conal artery (74.5%), what is similar to humans. The blood supply to the sinuatrial node more frequently (85.5%) was by a branch of RCA. Similar to the former, AV node artery most frequently arose from RCA (69.2%). The numbers of descending (rami marginales) RCA branches varied between 1-6, and their origin and distribution resembles the corresponding ones in humans. No statistically significant sexual differences in length and distribution pattern were present. This study shows that the anatomy of RCA or its branching patterns in monkey hearts are very similar to the humans. Key words: right coronary artery, anatomy, distribution, non human primate