Introduction: The comparison between the anatomical heart sheep and the human heart in a straight line shows a high degree of similarity; the dimensions of the heart sheep closely resemble the human heart. Materials and Methods: All analyzes and photographs taken from the sheep heart and human heart were performed in the laboratory of human anatomy, department of health and biological sciences, State University of Ponta Grossa. The morphometric analysis included 8 specimens heart study material pertaining to the anatomy lab UEPG. The sheep hearts were obtained from slaughterhouse taking into account the relative weight next to the human, between 60 and 70kg. Measurements were taken with digital calipers. Results: Internally it is possible to observe the macroscopic similarity between the atrial ventricular chambers of the sheep heart and the human heart. In a non-linear analysis, it can be concluded that they are distinct in complexity, as the human heart shown largest value of fractal dimension in relation to the sheep heart. Conclusion: The comparative study suggests more comprehensive use of the sheep heart as a model for anatomical study, due to its proximity to the human heart, but denotes the differences in complexity between the organs through the use of fractal dimension.