Background. Assessing the postmortem interval (PMI) is one of the most problematic issues in judicial practice. Objective. To investigate the morphological changes of uterus tissues to determine the PMI-dependent features of postmortem changes development. Methods. A morphological analysis of 40 uterus tissue samples was performed; consisting of two groups: first group – samples from the corpses of women aged 23 to 70 years (n = 34), second group – comparison group – biopsy material from 6 women with uterine prolapse, uterine leiomyoma, from unaffected areas. Results. In the period from 24 to 48 hours after death, there were changes in the form of a slight change in the structure of cellular elements, changes in their color, the presence of light gaps between connective tissue and muscle fibers. In the period from 48 to 72 hours, the destruction of the border between the muscular and serous membranes, blurred contours and ruptures of cells, severe swelling of muscle fibers, wide gaps between muscle fibers, a significant decrease in fibroblastic cells were observed. In addition, there was no endothelium in a significant number of vessels, loss of clarity of fiber bundles, lack of nuclei in a significant number of myocytes. Desquamed endothelial cells and hemolyzed erythrocytes were seen in the openings of most vessels. Conclusion. Histological examination of uterine tissues showed the presence of specific changes during the studied time intervals after death, which can be used to introduce criteria to determine the time since death in practice.