Abstract: For most of independent gold deposits, especially those of vein type, the ore mineral assemblages and mineral sequences are similar. It needs a reasonable explanation for the relation between such similarity and the tectonic pulsation. The explanation proposed by this paper is that, the mineral sequence in the mineralization is decided by the differentiation of ore-forming fluid system and the orderly deposition of each sub-system derived from the differentiation. The source of gold ore is actually an ore-forming fluid storeroom, in which the sub-systems of ore-bearing solution with various properties occur in different levels in the course of migration, differentiation and convergence.