Gas chromatography combined with mass spectrography (GC - MS) was used to analyze the content of Muscone, a form of natural Moschus in high purity, with N2 as the carrier gas and isopsoralen as the internal standard. Results: The linear range of Muscone was from 0.056 to 0.451 g/L, regression equation: y=0. 3454 x-0. 1076,r=0.9999,the recovery was 97.99%and its RSD was 5.0%. RSD of within - day precision was 3.85% and RSD of day - to - day was 2.20% . The contents of Muscone from three batches of natural Moschus were 1.82% (RSD= 2.50%) ,3.33%(RSD = 1.36%) and 4.40%(RSD3.85%) respectively. The method is simple, rapid, reliable, and can be used as quality control for Muscone of Moschus and its preparation.