Background: cesarean section is one of the most commonly performed surgical procedures in obstetric practice. It has become increasingly important to study the sequelae of this procedure on the future reproductive capacity. Special investigations are required for assessment of CS scar integrity to avoid its dehiscence or rupture during pregnancy or labor. Objectives: to compare between the accuracy of ultrasound and hysteroscopy in visualization of the site of Cesarean section scar in non-pregnant females and also to determine and comment on thickness, vascularity, continuity and ballooning of the scar. Patients and Methods: in a comparative cross-sectional study, 50 women with previous cesarean section attending the Ob/Gyne outpatient clinic complaining of infertility or recurrent pregnancy loss. They had been examined by transvaginal ultrasound (TVS), then by hysteroscopy to evaluate and compare their accuracy in assessment of the scar. Results: it was found that hysteroscopy can't comment on scar thickness but transvaginal ultrasound can do it in all patients of the study with a mean value 1.57 mm. There is a statistically significant correlation between the use of ultrasound and hysteroscopy in determination of the site, continuity and vascularity of scar, while there is a statistically insignificant correlation between ultrasound and hysteroscopy in determination of the balloning of the scar. Conclusion: ultrasound is more accurate than hysteroscopy in evaluating scar thickness and detection of scar defect.