Authors systematically collected 147 samples(at last constituting 100 samples for analysis) of Malan Loess in Loess Plateau and 54 elements were analysed for each sample.Abundance of each element was calculated by means of weighted average method.The results showed that chemical compositions of loess were very similar to each other in all parts of Loess Plateau with a good characteristic of homogenity.Moreover,the average chemical compositions of loess were very close to Clark values of crust,which are used at present.Therefore,the average chemical compositions of loess may be used to represent average chemical constituents of comtinetal upper crust.From theoritical point of view,typical eolian loess has a very large area of material sources and was also mixed homogeneously.Consequently,using it to calculate Clark values of upper cmst should be more reasonable,more representative and more substantial than previous methods.it could be a new way for investigation of Clark values of crust and a new field of loess geochemistry study in future.