Background: The rectal pathology is the one of the popular surgical diseases that leads to disorders of life style and as result to disorders of vital activity. Knowledge of morphology of the rectum is the base for understanding the etiology, techniques for diagnostic manipulations, treatment method, including a surgical intervention. This scientific work is aimed to define an ability to use pig as biomodel for experimental and clinical studies in order to develop new approaches of treatment of the rectal pathology. Materials and methods: For the research two groups were used. I group includes 50 humans (27 females and 23 males), II group includes 8 vietnamese pot-bellied pigs. The rectum of pigs and human were studied via traditional methods (description morphological and histological) and modern methods such as 3D reconstruction. Results: Topography, macroscopy, microscopy of pig`s and human`s rectum in comparative aspect are described in this article. With the help of traditional methods such as macroscopy and microscopy and modern methods, namely 3D reconstruction, the structure of the pig`s and human`s rectum was reconstructed. The morphological parameters, such as size of anorectal and rectosigmoid angles, the length of the rectum and its parts, were determinated. Macroscopy and microscopy discovered comperative structures of rectum of pig and human. Conclusion: Thus, it is proved that pigs can be used as biomodels in experimental and clinical studies for development the new methods of treatment the rectal pathology in humans.