Intertidal biofilms are essential to coastal trophic networks and affect the geological processes of intertidal sediments. Nutrient inputs promote their growth but anthropogenic pollution diminishes their functional capacity. Notwithstanding this, biofilms demonstrate resilience by mitigating environmental stresses at the land-sea interface. The resistance strategies utilized by this microbial consortia against elevated metal concentrations are intricate nonetheless, the transcriptome response of intertidal biofilms to cobalt is still inadequately investigated. This study aims to reveal the molecular mechanism employed by this microbial community in response to cobalt stress.