Objective: to evaluate the diagnostic accuracy of Transvaginal Sonography (TVS) in detection of intrauterine abnormalities with two Dimensions (2D) and three Dimensions (3D) compared to hysteroscopy in women with history of secondary infertility. Patients and Methods: The study was conducted in Kasr El Aini hospital. Cases were recruited from the outpatient gynecological clinic. 40 cases were included in the study in the period between February 2009 and July 2009. They were recruited based on their complaint which was secondary infertility (infertility after full term &infertility after abortion); all patients underwent transvaginal ultrasonography using an Accuvix & Voluson machines with a vaginal probe, The uterus was examined in longitudinal & transverse planes (2D transvaginal ultrasound) and the 3 coronal planes (3D transvaginal ultrasound), then Hysteroscopic examination was done for all cases using rigid panoramic type. Results: Compared to Hysteroscopy, the sensitivity, specificity, PPV, NPV and total accuracy of 2D US were 75%, 93.8% 94.7%, 71.4%, and 82.5% respectively and for 3D US giving 83.3%, 93.8%, 95.2%, 78.9% and 87.5%. Conclusion: Routine use of TVS (2D & 3D) in diagnosing uterine cavity abnormalities is satisfactory and consequently is becoming a basic tool in investigating infertile patients. Hysteroscopy which is the gold standard in investigating the uterine cavity should be used to confirm the findings of TVS and also when TVS gives doubtful results.