Background: Splenic metastasis are typically associated with peritoneal seeding and multi-organ involvement in advanced ovarian cancer. Although splenic parenchymal lesions are classified as International Federation of Gynecology and Obstetrics (FIGO) stage IVB, they are usually surgically resectable. The aim of this study was to evaluate the patterns and prognostic significance of splenic parenchymal metastases in advanced ovarian cancer. Methods: We conducted a retrospective review of medical records of patients who underwent splenectomy as part of cytoreductive surgery for advanced ovarian cancer between 2007 and 2018. The patients were categorized into two groups based on the presence of parenchymal invasion or capsular/hilar invasion. Clinical characteristics, including histological invasion patterns, and survival outcomes were analyzed. Results: A total of 110 ovarian cancer patients underwent splenectomy: 55 (50%), 40 (36.4%) and 15 (13.6%) patients underwent splenectomy during primary debulking surgery, interval debulking surgery, and disease recurrence, respectively. The median age was fifty-five, and all patients had FIGO stage IIIB–IV disease. A total of 33 (30.1%) patients had splenic parenchymal invasion, and all lesions were accompanied by capsular or hilar metastasis without solitary parenchymal invasion. Among the patients with primary disease (n = 95), 43 (45.3%) had stage IV disease, including 33 (30.1%) with splenic parenchymal metastasis. There were no significant differences in progression-free survival (p = 0.698) and overall survival (p = 0.928) between patients with parenchymal invasion and those with capsular/hilar metastasis. Conclusions: Although splenic parenchymal metastasis shows widespread tumor dissemination, splenic parenchymal metastasis was consistently associated with capsular or hilar involvement, suggesting surgically treatable disease. The prognosis of splenic parenchymal metastasis was comparable to that of capsular or hilar invasion, warranting its consideration as FIGO stage IIIC disease.