The thyroid gland is an integral part of the complex anatomy of the equine neck. Transcutaneous ultrasonography provides a non-invasive method for assessing the thyroid glands parenchyma and dimensions in horses. This study evaluated 30 clinically healthy Turkmen horses whose health status was confirmed through comprehensive physical examination, complete blood count, serum biochemical analysis, and thyroid hormone analysis. The horses were divided into two age groups: Group 1 under 36 months (three males and eight females), and Group 2: Thirty-six months and older (eight males and eleven females). Ultrasonographic assessment of the thyroid region was performed using a high-frequency linear transducer. Each thyroid lobe was systematically evaluated for its dimensions, volume, morphology, contour, parenchymal echogenicity and echotexture. Statistical analysis revealed no significant age-related differences in thyroid parameters; however, sex-based differences were observed: females had significantly greater thyroid lobe length and volume on both the left and right sides compared to males. Qualitative B-mode ultrasonography showed consistent morphological features; in the longitudinal view, all thyroid lobes exhibited a flattened, oval shape. On transverse images, most lobes (83.93%, n = 47) appeared elliptical, while the remaining lobes (16.07%, n = 9) were spherical. Irrespective of shape, all thyroid lobes demonstrated regular contour margins. Regarding echogenicity, most lobes were hyperechoic, with a few being isoechoic, relative to the sternocephalic muscle. Furthermore, all thyroid lobes exhibited homogeneous to mildly heterogeneous echotexture. This study establishes diagnostic baselines for thyroid evaluation in the Turkmen horse breed aiding in the detection and management of thyroid pathologies.