Abstract: The biodistribution of the 89SrCl2 solution with different amount carrier are studied. The results show that 89Sr is concentrated in bone mostly, up to maximum within 24 h, and the concentration of 89Sr in bone is affected obviously by the amount of SrCl2 in the 89SrCl2 solution. The bone concentrations of the group of high specificactivity (maximum is 80.2 ID%/g) are always higher remarkably than those of other groups (SrCl2 concentration is 0.1?0.5?2.5 and 100 g/L) in 7 days. The SrCl2 has toxicity, the half dosage caused death is about 3 mg for normal mice and the safety dosage is <1 mg.