Introduction: Splenosis is the autoimplantation of ectopic spleen tissue in various anatomic cavities of the body resulting after trauma or rupture of the splenic parenchyma. The major localization sites of this phenomenon are mainly intraperitoneal, the gastrenteric tract, genitalia, intrahepatically and the kidneys. Extraperitoneal locations occur less frequently and include the thorax and brain. Also locallization in the subcutaneous fat has been described. Case report: We present the case of a 32-year-old woman with symptomatic peritoneal cavity splenosis occurring ten years after traumatic splenectomy. The patient was admitted to our department with the clinical presentation of an adnexal tumor. US and CT confirmed an adnexal mass. Exploratory laparotomy was performed and multiple focal lesions were noticed on the uterus, ovaries and intestinal tract. Biopsies were taken and sent for histological analysis. The pathology specimen revealed ectopic splenic tissue. After surgical intervention the patient remained asymptomatic. Conclusion: Splenosis is a rare phenomenon which clinicians should be aware of in order to spare patients from pointless surgical interventions. Patients with abdominal masses and post-traumatic splenectomy should be checked for splenosis.