The El Niño Southern Oscillation (ENSO) has a significant impact on Australia’s climate. It also impacts ocean temperatures and salinities in some regions around Australia, but it is unclear how it impacts biological productivity in the oceans. This study uses Integrated Marine Observing System (IMOS) National Reference Station (NRS) data over a period of over 10 years (2008-2022) to investigate the ecological impacts of the ENSO on coastal plankton communities in the East Australian Current (EAC). Four NRS sites within the EAC obtain monthly samples and span across two plankton provinces, including the Great Barrier Reef (Yongala and North Stradbroke Island) and Temperate Neritic (Port Hacking and Maria Island). We reveal that at all four of these NRS stations, phytoplankton abundance and phytoplankton biomass both increase during a La Niña phase of ENSO. In contrast, zooplankton biomass and zooplankton abundance at the NRS show a range of responses to ENSO. Understanding the response of plankton to changes in ENSO phase has important implications for fisheries and is part of the wider understanding of the impacts climate teleconnections will have on marine ecosystems.