Background Hysteroscopy is considered the gold standard for detecting diseases of the uterine cavity. It is simple, safe, and can be performed in an outpatient clinic. Although endometritis is not clinically clear, it may lead to infertility. Moreover, there is strong evidence that endometritis may lead to a premature spontaneous birth. Aim This study aimed to assess the diagnostic value of diagnostic hysteroscopy in patients with chronic endometritis. Patients and method The current study was performed on 50 women with unexplained infertility. All patients presented to the outpatient clinic of Tanta University Maternity Hospital in the follicular phase of menstruation. Results Hysteroscopic findings in the form of hyperemia, edema, micropolyps, and dark blue spot suggesting chronic endometritis were found in 31 cases. Histopathological examination confirms the diagnosis of chronic endometritis in 28 cases by detection of plasma cells in the endometrial biopsy. Microbiological examination showed a positive growth in 17 cases by detection of organisms in the endometrial biopsy; 1 of them showed positive chlamydial infection and 4 cases of mycoplasma in the multiplex polymerase chain reaction test. There was a significant association between hysteroscopic picture suggesting chronic endometritis and its confirmation by histopathological examination of endometrial biopsy. Conclusion Hysteroscopy is a convenient examination for detecting chronic endometritis. It could be applicable for investigating asymptomatic infertile patients. Antibacterial, antichlamydial, and antimycoplasma drugs have a good result in chronic endometritis. Endometrial dyeing with methylene blue at hysteroscopy improves the detection of chronic endometritis. More studies are recommended for endometrial evaluation by hysteroscopy.