Hyperproliferative pathology of the uterus (HPЕ) occupies one of the leading places in the structure of female infertility, leading to women’s generative dysfunction in 80% of cases. The aim of the study: to assess the immunohistochemical and morphological features of the endometrium in patients with hyperproliferative pathology of the endometrium and infertility. Materials and methods. Forty endometrial samples from women with infertility and hyperproliferative pathology of the endometrium were examined: 20 samples of endometrium obtained from women with infertility and endometrial polyps (1 group) and 20 samples obtained from women with infertility and endometrial hyperplasia without atypia. The endometrium of 20 healthy women was examined as the control group. Pipelle biopsy of the endometrium was performed in the luteal phase of the menstrual cycle in women of the main and control groups to obtain the material. The morphological and immunohistochemical features of the endometrium in women with infertility and hyperproliferative pathology of the endometrium were determined. Histogram sections were stained with hematoxylin and eosin, and picrofuxin (Van Gizon’s stain). An immunohistochemical study was performed with the polymer detection method of antigen application using the UltraVisionQuanto peroxidase polymer and DAB plus chromogen detection system to determine the expression of monoclonal antibodies to estrogen and progesterone receptors, natural killers СD-56 and СD-138. The results of the investigation. Morphological examination of the endometrium of women with infertility and hyperproliferative pathology of the endometrium revealed a number of pathological changes: glandular and glandular-fibrous polyps of the endometrium (70–80%), atypical endometrial hyperplasia (10–20%), dyschronosis of endometrial receptivity (40–50%), morphological signs of chronic endometritis, positive expression of CD-138 (10%), as well as their combination. Conclusions. Women with infertility and hyperproliferative pathology of the uterus and unsuccessful attempts at ART have expressed dyshronosis of receptivity of the endometrium on the background of reduced expression of endometrial natural killers and positive expression of CD-138. It is indicative of the dysregulation of immunological homeostasis on the local level, which may be the cause of disruption of blastocyst implantation processes, unsuccessful attempts of ART and lead to early pregnancy loss.