Australia has an advanced marine protected area legislative framework, however, with the evolving threats to the ocean environment, effectiveness of current laws must continually be examined. One of the regulatory challenges, in a federation such as Australia, is the fragmentation of the legal landscape across the eight states and territories. This is in part an historical legacy and can allow different jurisdictions to address localised issues. However, given the interconnectedness of the marine environment and many activities within it, it is important that legal protections and management approaches do not differ unnecessarily across anthropocentric politico-legal boundaries. Inconsistencies between jurisdictions create a complex legal landscape, which adds a regulatory burden for intra-state actors and activities, and may also weaken cooperation between authorities hindering the protection regime. This article comparatively analyses Australian state and territory legislation, by examining the differences between, and strengths and weaknesses of, each. The analysis illuminates the marine protected area legal landscape in Australia, highlights how these laws may be harmonized, and identifies the legal provisions that might be included in a best practice marine protected area statute. The article contributes to the growing body of literature analysing marine protected area legal frameworks to enhance sustainable marine protection, management and utilisation. In doing so the research will be of value to Australia and other countries facing similar challenges.