Background: Robert’s uterus is a rare müllerian duct anomaly described as an asymmetric septate uterus with a noncommunicating cavity. Its main presentation is recurrent cyclical abdominal pain. However, patients with Robert’s uterus may present with recurrent pregnancy loss and infertility. Case: We herein report a rare presentation of Robert’s uterus in a 23-year-old woman who suffered from primary infertility without a history of dysmenorrhea. Preoperative two-dimensional ultrasound (2D-US) suggested that the patient only had a partial septate uterus. A hysteroscopy found only the right side of the uterine cavity with a narrow channel while the left uterine cornua and left tubal ostium were not visualized. Intraoperative transabdominal 2D-US confirmed that there were two uterine cavities, a blind hemi-cavity, and a contralateral communicating hemi-cavity. Subsequently, the asymmetric septum was successfully removed by ultrasound-guided hysteroscopy. Conclusion: For patients diagnosed with septate uterus by 2D-US, three-dimensional ultrasound or magnetic resonance imaging is required to make a definitive diagnosis and to help with surgical planning. If results are inconclusive, intraoperative ultrasound-guided hysteroscopic metroplasty may be a reliable pathway for the definitive diagnosis and treatment of Robert’s uterus.