Marine industries include fisheries, shipping, aquaculture, and offshore energy, among others, which are an important component of the global economy. These industries raise severe sustainability challenges, including overfishing, pollution, habitat destruction, and climate-related risks. Financial technology, or Fintech, may be the key to transforming these sectors through innovative, efficient, and scalable financial solutions. This chapter explores where Fintech and sustainable finance intersect in marine industries, discussing how blockchain technology, artificial intelligence, and decentralised finance can be used to provide transparency, resilience, and inclusivity. The chapter discusses how Fintech is promoting economic empowerment and environmental conservation in coastal and marine-dependent communities by examining the role of blue bonds, crowdfunding platforms, and digital payment systems. Marine industries involve fishing, shipping, aquaculture, and offshore energy. Other challenging sectors of the world economy include overfishing, pollution, habitat destruction, and risk due to climate change. Fintech has enormous potential for changing everything mentioned above by using innovative, efficient, and scalable financial solutions. Ultimately, this sees the future of Fintech in marine sustainability as well. It has newer trends, such as digital twins, IoT integration, and AI-enhanced financial tools. Fintech shall help the marine industries evolve towards a sustainable blue economy.