This study was conducted to reveal the anatomical and histological features of left and right septomarginal trabeculae in the heart of the Hatay mountain gazelle. In the study, two female and two male adult Hatay mountain gazelle hearts were used. For this purpose, the materials detected in 10% formaldehyde solution were stained with Crossman's modified triple staining technique and examined under a light microscope after anatomical examinations and measurements were made. The presence of trabeculae in both ventricles was demonstrated. While the number of septomarginal trabeculae was 1 in each of the samples in the right ventricle, it was determined that it was 2 in each of three hearts and 3 in one heart in the left ventricle. It was observed that the right trabeculae were unbranched and fleshy, while the left trabeculae were filamentous and mostly branched. The lengths and thicknesses of the right trabeculae were measured 12–17 mm and 3–4 mm and the lengths and thicknesses of the left trabeculae were measured 6–15 mm and 0.5–1 mm. In the histological examination of both trabeculae, connective tissue, Purkinje fibres and blood vessels were observed, in addition, it was detected that the right trabeculae had myocardial fibres. Few capillaries were found in the left trabecula, while both more capillaries and blood vessels were found in the right trabeculae.