Abstract: With the further implementation of the international shipping greenhouse gas reduction strategy,clean marine fuels have become the core direction for the shipping energy transition due to their low-carbon emission characteristics.However,the complex properties of clean marine fuels significantly increase the leakage risks and impose higher demands on fuel leakage monitoring technologies for ships. Existing traditional leakage monitoring methods still have limitations in high-concentration gas detection,anti-interference detection in multi-media environments,and high-precision micro-leakage detection,making it difficult to effectively meet the monitoring requirements for clean marine fuel leakage. To address these issues,this study analyzes the application characteristics of different clean fuels,the leakage characteristics in various physical states,and the monitoring requirements for different leakage patterns. It also explores key future directions for novel sensors,including the development of anti-saturation MEMS combustible gas sensors that use three-dimensional porous structure designs and low-power dynamic power management technology to address sensitivity attenuation in high-concentration environment; the design of anti-interference pipeline thickness sensors based on multi-frequency pulsed eddy current signal feature extraction and multi-media interference inversion models to improve crack detection accuracy; and the development of thermal micro-flow sensors that use adaptive quantitative safe acquisition technology and low-pressure-loss flow-rectifying structures to achieve high-precision micro-leakage monitoring. This study provides insight into the development of clean fuel leakage monitoring technologies for ships and supports the green and safe development of the shipping industry.