Abstract: Taking port cargo throughput and container throughput as the research subjects, this paper uses the primacy index, rank-size law and kernel density to examine the port scale distribution in theYangtze River Delta.Some results are obtained as follows. (1) The port scale distribution in the Yangtze River Delta changes from primary distribution to rank-size distribution. The grade distributions of freight transport and container transport are inherently consistent, but there are some differences in evolution trend and period. Yangtze River Delta hub evolves from a single core hub to dual-core hubs, and the triple hub ports maybe formed in the future. (2)Yangtze River Delta port scale distribution is gradually optimized, and its hierarchical structure tends to be reasonable.The port system basically satisfies the rank-size distribution, but has not reached the ideal situation.(3)Kernel density curves of cargo throughput and container throughput change from multi peak into double structure and single structure respectively. This means both freight transport and container transport are moving in a coordinated direction.