Marine organisms represent a rather unexplored source of new activity and biological functions of molecules for biotechnologies. The research in chemical ecology of the marine environment leads to looking at metabolites of recognition or defence produced by these models. Marine bacteria belonging to the Pseudoalteromonas genus of the Gammaproteobacteria class are often found in association with marine eukaryotes, and their ability to produce a variety of biological activities attracted a particular attention. The marine Pseudoalteromonas sp. 3J6 and D41 were selected for their capacity to inhibit the biofilm formation of other bacteria. The study of antibiofilm metabolites synthesised by marine bacteria 3J6 and D41 biofilms can lead to the development of new anti-fouling compounds or applications in surface hygiene. The main originality of these compounds is to be specifically antibiofilm, they have no activity against planctonic bacteria.