This paper reviews the progress in the study of marine biogeochemical processes of biogenic elements (C, N, P, S, Si) and consists of four parts: 1. The cycling of biogenic elements in the euphotic zone The air-sea exchange process of biogenic elements is an important link in the euphotic zone cycle. The interface behaviors of some trace gases which can affect global climate and the possible influencing factors (mainly referring to biological processes) are discussed. The exchange of carbon between atmosphere and ocean depends on the CO2 partial pressure (PCO2) difference; DMS is mainly released from the sea. PCO2 and DMS are controlled by biogeochemical processes to some extent. These results are useful to understanding systematically the importance of the ocean in global climate change. The euphotic zone is the most active region in the marine biogeochemical processes of biogenic elements. Phytoplanktons transform DIC into DOC by photosynthesis, absorbing nutrients (N, P, Si) in certain proportion. On the other hand, they are generally eaten by mesozooplankton and macrozooplankton, and are then excreted as sinking fecal pellets, some of them are decomposed and disolved again, others off the euphotic zone, including regenerated nutrients in mid-or deep-ocean, may be brought to upper water by upwelling. The processes of cycling and regeneration of biogenic elements in the euphotic sea are very complicated. 2. Marine biogeochemical process of particulates Important information concerning the biology, chemistry and geology of particulates can be obtained by studying their component variations, vertical fluxes and transport mechanism. By discussing the component variations with space and seasons, the particulates origin and function in transporting and storaging biogenic elements are reviewed. There are two main factors cited to explain the changes of vertical fluxes-biology and physics, such as the contribution of diatom bloom to exportable organic matter from the upper water, the influences of wave, lateral transport, El Nino/Southern Oscillation. The vertical transport mechanism of particulate matter tends to be dominated by the biogeochemical cycle. 3. The behaviour of biogenic elements near the sediment-water interface The exchange amount across the sediment-water interface is large. The fluxes from sediment to water in global oceans, Nansha lagoons, Xiamen western sea, etc. and the carbon fluxes to the sea floor in the Scheldt River estuary and Chesapeake Bay are summarized. The exchange processes keeping the interface ecological system balance and the behavior differences reflecting the different environmental characteristics are discussed on the basis of thermodynamics and kinetics theory, e.g. redox balance, percipitation-dissolution system, diagenetic process. In addition, the biological process affecting interface behaviours, such as phytoplankton and benthos bioturbation which strengthens the exchange between the water and sediment, are mentioned. 4. Role of small organisms in the marine biogeochemical cycle of biogenic elements Recently, small organisms (mainly referring to phytoplankton and bacteria), have been paid much more attention. Due to the finding of the microbial loop, the contribution of bacteria producers appear to be much greater than thought before. First, microorganisms are important storers of POM, especially in the eutrophic zone. Second, they can utilize biogenic elements. As decomposers, their contributions lie in returning the "lost" energy to the food chain. This is one of the key links in the biological process which controls elements cycling.