To quantitative assess the differential between cerebral microbleeds and calcification in susceptibility weight imaging mapping. We quantified the magnetic susceptibility value of calcifications and cerebral microbleeds(CMBs) in susceptibility weight imaging mapping. Significant difference of magnetic susceptibility value was found between them. The 95% confidence interval for the magnetic susceptibility value of the calcification and CMBs was different. The optimal threshold to detecting CMBs was selected by receiver operating characteristic. The conclusion was that magnetic susceptibility value can used to differential diagnose cerebral microbleeds and calcification in the susceptibility weighted imaging mapping.