By the analyses of the changed characteristics of the heavy minerals and sandstone-formation ratio at dif- ferent tectonic acting stages of Eogene thrust structure phase in the southern margin of Junggar Basin. The evolution laws of the provenance system in the phase are explored. The studies show that the developed provenances number gradually increased from the initial period of the intensive activities to the peak period, and the distance to the provenances is more and more closer; while the number and distance for the provenances from the peak to the quiescent period are just on the contrary, and moreover the supplied sediments are gradually reduced.