AIM: To compare the antitumor activity of spore polysaccharides (GI-SP) and broken spore polysaccharides (GI-BSP) from spores of Ganoderma lucidum (Leyss ex fr) Karst. METHODS: BALB/c mice were implanted with Sarcoma 180 and administered intragastrically with Gl-SP or G/-BPS (50, 100, 200 mg/kg)respectively for 14 d. At the end of experiment, the tumor were removed and weighted. At the same time, spleens of tumorbearing mice were prepared to observe the effect of Gl-SP and