Abstract: Scanning electron microscopy (SEM) is an important tool for marine geological research, enabling detailed analysis of the morphology and composition of the samples. The complexity and diversity of marine geological samples require specific pretreatment techniques to ensure high-quality images and reliable data. We systematically reviewed the SEM pretreatment methods for typical marine geological samples, including foraminifera, ostracods, coccolithophores, spore-pollen, iron-oxidizing bacteria, cold-water corals, powdered sediments, and rock fragments. The main procedures including cleaning, ultrasonic treatment, drying, fixation, coating, and instrumental analysis were described in detail based on the physical and chemical properties of each sample type (e.g., fragility, high water content, poor conductivity). Common challenges, such as electron charging effects and structural collapse, were addressed with optimization strategies. Results demonstrate that optimized pretreatment protocols could greatly improve the SEM imaging resolution and data reliability, providing a robust reference for marine geological microanalysis.