Abstract: Thirty surface sediment samples were collected from the central Bohai Sea in May 2015.Total organic carbon (TOC), total nitrogen (TN), total phosphorus (TP), biosilicon (BSi), organic matter (OM) and moisture content (MC) were analyzed to understand distribution characteristics of biogenic elements of the surface sediments from the central Bohai sea and further reveals the contribution of organic matter sources and marine biogeochemical processes.The contents of biogenic elements were 0.21%~1.43% for TOC, 0.01%~0.12% for TN, 0.01%~0.04% for TP, 0.08%~0.46% for BSi, 1.43%~9.42% for OM and 18.24%~47.70% for MC, respectively.The distribution patterns of TOC, TN, TP, OM, and OM were similar, reflected by lower in the east and higher in the west.However BSi was higher in the middle of the central Bohai Sea.Organic matters were originated from mixed inputs of terrestrial and marine sources and mainly form the terrestrial sources based on the molar ratios of TOC/TN.Diatoms contributed a lot to the total primary productivity based on TOC/BSi ratios.Results from the sediment quality evaluation showed that the surface sediments were contaminated to some extent, and TOC and TN were over class Ⅱ standards in some sea areas of the central Bohai Sea based on sediment quality assessment criteria of the Department of Environment and Energy of Ontario, Canada.