Marine biodiversity is increasingly recognized as a critical indicator of environmental health and sustainability, yet its integration into Life Cycle Assessment (LCA) remains underdeveloped. This systematic review synthesizes 30 studies that evaluate and contribute to the development of marine biodiversity impact assessment within LCA, including studies that propose preliminary impact pathways or alternative biodiversity loss metrics, develop and operationalize new pathways or refine already established LCA indicators. The review examines their geographical and temporal coverage, impact pathways and sectoral and taxonomic representation. Results reveal fragmented research efforts, with greater attention devoted to fisheries and offshore wind farms sectors and their related impacts and indicators, while other major marine sectors (e.g. shipping) remain unexplored. Similarly, when it comes to impact pathways and indicators, marine eutrophication is already fully operational and integrated as an LCA indicator with a consolidated modelling framework, whereas other key pressures responsible for marine biodiversity loss (e.g. invasive species) remain underdeveloped and marginally addressed, as they often lack comprehensive ecological datasets and LCA inventories. Taxonomic coverage is centered on commercially important or easily monitored groups, while some foundational taxa, primary producers and microorganisms remain underrepresented. The functional dimension of organisms and ecosystems is not yet accounted for and cumulative impacts are not yet operationalized due to inconsistent units and mismatched scales. In addition, the scarcity of long-term assessments limits our understanding of the delayed responses of marine organisms to chronic exposures to impacts. Overall, current LCA approaches risk to misrepresent marine biodiversity loss due to incomplete taxonomic, spatial and ecological information, highlighting the need for more ecologically comprehensive biodiversity impact assessments frameworks.