The aim of this study was to determine the normal coelomic structures of a healthy red-eared slider (Trachemys scripta elegans) and yellow-bellied sliders (Trachemys scripta scripta) using magnetic resonance images and gross cross-sectional anatomy. Three- or six-centimeter thick, T1-weighted and T2-weighted images were obtained from three live adult red-eared (n = 1) and yellow-bellied sliders (n = 2) with a 1-Tesla superconducting magnet and a surface coil. Magnetic resonance imaging was performed in transverse, sagittal, and dorsal planes. Images of the coelomic cavity were compared to frozen, cross-sectional cadaveric anatomy of the same turtles. Anatomic structures were identified and labeled. Resulting images presented excellent, detailed information of coelomic structures. The intent of this study was to develop an atlas of cross-sectional anatomy and magnetic resonance appearance of the normal coelomic cavity in red-eared and yellow-bellied sliders that can be used as a reference for the interpretation of any cross-sectional modality.