The aims of this study were to assess if ECG-gated 16-multidetector CT (MDCT) provides sufficient temporal and spatial resolution to evaluate canine coronary arteries and provide a detailed description of their anatomy. A total of 24 dogs were included. Images were reviewed to assess: (1) coronary artery opacification and dominance; (2) choice of optimal R-R ECG reconstruction interval for both left coronary artery (LCA) and right coronary artery (RCA); (3) branching patterns of the left main coronary artery (LMCA); and (4) diameter and length of the LCA and RCA and classification of their branches by adapting a previously described segmental coding system. The degree of opacification of the coronary arteries was subjectively judged as excellent or good in five and 19 dogs, respectively. All hearts showed a left coronary dominance. The best R-R reconstruction interval for both LCA and RCA arteries was 75 per cent. Seven different subtypes of LMCA branching patterns were noted. The and were divided into three angiographic segments, and the and the RCA in two and three segments, respectively. ECG-gated 16-MDCT coronary angiography provides adequate resolution to assist the basic anatomy of the main coronary artery branches.