Barnacle (Balanus amphitrite) settlement on synthetic hydrogels with various chemical structures was tested in laboratory assays. The results demonstrated that cyprids settle less or not at all on hydrogels and PDMS elastomer compared with the polystyrene control. The low settlement on gels is most likely due to the 'easy release' of initially attached cyprids from the gel surfaces. This low adhesion of cyprids is independent of surface hydrophilicity or hydrophobicity, and of surface charge. The results also revealed that hydrogels can be categorized into two groups. One group showed an extremely strong antifouling (AF) performance that was independent of the elasticity (E) or swelling degree (q) of the gels. The second group showed relatively less strong AF performance that was E- or q-dependent. In the latter case, E, rather than the q, may be the more important factor for cyprid settlement.