Abstract: AIM　To study the pharmacokinetics of the new tumor radiosensitizer glycodidazolum natrium(CMNa) in tumor patients after single- and multiple-dose, in order to evaluate the accumulation of CMNa in patients. METHODS　5 tumor patients were given an intravenous dose of CMNa 700 mg/m² every other day for 9 times, and blood samples were collected at designed time after the first and the ninth CMNa administration. The blood concentrations of CMNa were determined by HPLC-UV. The blood concentration-time curves of CMNa after single-dose and multiple-dose were fitted to a two-compartment open model. RESULTS　CMNa was found to be distributed and eliminated rapidly in patients whether after single- or after multiple-dose. The blood concentration-time curves and pharmacokinetics parameters between single-dose and multiple-dose were similar, and they showed no significant difference. CONCLUSION　CMNa will not accumulate in patients′ bodies, and it is a safe drug.