Abstract: A new method was established to determine the content of 10-O-(N, N-dimethylaminoethyl)-ginkgolide B methanesulfonate by ¹H NMR using DMSO-d₆-D₂O(5 ∶1)as the solvent and zidovudine as the internal standard. Experimental parameters of NMR were extensively investigated. Under the optimal condition, the sample and internal standard showed good separation and linearity. The content of 10-O-(N, N-dimethylaminoethyl)-ginkgolide B methanesulfonate was 99. 12% and its RSD was 0. 16%. This method is specificity, accurate, simple and rapid, and is suitable for the quantitative determination of the content of the reference substance content.