Abstract: In this paper the micro-distribution patterns of trace elements in the Nandan iron meteorite are studied by a synchrotron radiation X-ray fluorescence micro-scanning method (SRXRFMS).On the basis of our experimental results the classification,origin,evolution and other aspects are discussed.It seems reasonable that the Nandan iron meteorite should be classified to the group IAB.Further,it might be formed from the source matter with the chondritic composition,which experienced the impact and partial melting.