Study Objective To present a case of primary solitary large anterior abdominal wall leiomyoma Design Leiomyomas are said to be the most common benign tumor of the female reproductive tract. They are frequently found in the uterus, however they can also be found in the broad ligament, ovaries, fallopian tubes, vagina and, very rarely, on the abdominal wall. Abdominal wall leiomyomas are rare and usually thought to be associated with previous surgical resection of uterine myomas. Setting The patient was placed in lithotomy Trendelenburg position and under general anesthesia. Patients or Participants N/A Interventions Robotic-assisted mass excision was performed, and the specimen was carefully removed from a mini-laparotomic incision. Measurements and Main Results A 42 year-old woman, with no history of prior uterine surgeries, presented with a lump in the right lower abdomen which had been progressively increasing in size for months. Ultrasound revealed an anterior abdominal mass, with a diameter of about 9 cm, with no evidence of uterine myomas or ovarian tumors. To exclude the possibility of malignancy, the patient underwent robotic-assisted mass excision. Histopathology of the anterior wall mass showed a leiomyoma with diffuse coagulation tissues (weighted at 213 g). Conclusion Abdominal wall leiomyoma is an uncommon finding and is thought to be related to seeding following uterine myomectomies; however, the patient in this case had never undergone any uterine surgeries. The precise cause of the origin of primary abdominal wall leiomyoma is not clear at present. Transformation of the smooth muscle cell of the vessel wall in the anterior abdominal layer to leiomyoma may play a role. It is hypothesized to be associated with somatic mutation or interaction of hormonal and growth factors. In conclusion, benign primary leiomyoma of the abdominal wall is a differential diagnosis to be considered in women with an anterior abdominal mass and no histories previous uterine surgeries.