Abstract: The stability,immunocompetence and cytotoxicity in tumor as well as tumor inhibiting rate of 186,188 Re SZ39 are investigated. The results indicate that 186,188 Re SZ39 is stable in vivo by imaging and the volume of tumor of nude mice reduced obviously. So 186,188 Re SZ39 has a strong cytotoxicity effect against glioma cells and is of good prospect as immunoradiotherapeutic agent.