This article describes the vertical distribution of diatom taxa and their abundance in two sediment cores collected from Suzhou Creek.２１０Pb analysis was used to estimate the sedimentary rate of the two cores. The dominant genera in the cores were Cyclotella, Aulacoseira, Navicula, Coscinodiscus and Synedra, and the dominant species were Cyclotella meneghiniana, Navicula pupula and Aulacoseira varians. The diatom abundance in the two cores had similar trends, that is, the highest abundance occurred in the upper layers, with a range of 4.04～25.18×１０４ individuals/g.The bottom layers had a range of 1.41～4.43×１０^４ individuals/g, and the lowest abundance occurred in the middle layers (with a range of 0.91～2.30×１０^４ individuals/g). No obvious trend was found for the species richness in either column; however, the lowest species number occurred in the middle layers of the sediments, which corresponded to the decades between the 1960s and the 1980s. The results of a linear regression showed that the organic matter content was positively correlated with diatom abundance (p<0.01) in both cores. Our results indicate that diatoms in the sediments can be used to trace the pollution history of Suzhou Creek. During the 1940’s, the high abundance of diatoms in the bottom sediments indicated mildly eutrophic conditions. However, due to industrial pollution, the water quality deteriorated from the middle of the 1950’s to the 1980’s, and this is indicated by the decrease in diatom abundance in the middle layer of the sediments. The increase in diatom abundance in the upper layer of the sediments indicates the water quality improvement since the 1990’s, which is related with the intensive implement of restoration efforts in Suzhou Creek.