Abstract: The tumor-bearing mice are treated with ~(188)Re-CL58 by radioimmunotheray(RIT). The tumor controlling effect and drug distributing characteristics are observed. The results show that the uptake of tumor are more than that of normal tissue. The tumor suppressions effects of multiple low dose (MLD)-RIT group are more significantly than those of single high dose (SHD)-RIT and control group. MLD-RIT group suffers less weight loss and the least less-weighted tumors than control group and SHD-RIT group (P<0.05). For the numbers of metastatic foci, MLD RIT group have also less than both control group and SHD group (P<0.05). Tumors of MLD-RIT group absorbed more radiation dose than SHD-RIT group after injected the same dose of ~(188)Re-CL58. It may bring a conculsion that the curative effect of MLD-RIT is better than that of SHD-RIT.