Histiocytic sarcoma (HS) of spleen is a rare and potentially lethal condition. we reported a patient with thrombocytopenia of unknown etiology, multiple splenic lesions, and disseminated bone metastasis treated by laparoscopic splenectomy. The final pathologic diagnosis showed low-grade HS of the spleen. It's very rare that HS happened in a setting without splenomegaly.