Abstract: Photo-crosslinkable antifouling compositions, in particular antibacterial, antifungal and anti-algae ones, which include the combination of at least one telechelic oligoisoprene of a particular formula with an agent for crosslinking the oligoisoprene. The antifouling film is obtained by applying a thin layer of such a liquid composition on a substrate and is crosslinked at room temperature by exposure to visible and/or UV radiations. The film can be used for preventing the occurrence of a biofilm on any surface in a humid or aqueous environment, and can be used as an additive for preparing materials with a view to imparting bacteriostatic and/or bactericidal properties thereto.