Abstract: Dimethylsulphioniopropionate (DMSP) is the most abundant sulfur source in the ocean and firstly isolated from marine algae. The volatile metabolic product of DMSP, dimethyl sulfide (DMS), is the key factor in atmosphere that influencing global climate. Currently, various synthetic and metabolic pathways were detected in marine algae and bacteria, but it is still unknown how different pathways were chosen and how the metabolic products affect algae-bacteria interactions in phycosphere. This review summarizes the synthetic and catabolic pathways of DMSP in different marine organisms, and the possible action mode of DMSP in marine environment, especially in algae-bacteria interaction. As the key signaling molecular in phycosphere, DMSP may regulate algae-bacteria interaction through various pathways, such as chemotaxis, quorum sensing, or antibiotic synthesis.