Splenic vascular tumors represent a wide spectrum of lesions, ranging from benign to highly aggressive neoplasms. Among benign tumors, localized hemangiomas are the most frequent. Splenic hemangiomatosis is currently considered a diffuse variant of hemangioma, characterized by total or subtotal replacement of the splenic parenchyma by a vascular proliferation featuring the usual morphological findings of hemangioma. To the best of our knowledge based on a review of the medical literature, less than twenty cases have been described. Moreover, pediatric cases are absolutely exceptional. We report two new cases of splenic hemangiomatosis respectively occurring in a 1-year-old child and in a 30-year-old woman, with particular attention to the histological and immunohistochemical findings; related problems of differential diagnosis are also discussed.