Abstract: Over billions of years, the ocean has been regarded as the origin of life on Earth. The ocean includes the largest range of habitats, hosting the most life-forms. This review deals with the research and development work investigating the occurrence and bioprocessing of marine microbial enzymes. Competition amongst microorganisms for space and nutrients in the marine environment is a powerful selective force which has led to evolution. The evolution prompted the marine microorganisms to generate multifarious enzyme systems to adapt to the complicated marine environments. In this review, starting from the analysis of these featuring habitat-related properties, important examples of marine enzymes in biocatalysis will be reported. Therefore, marine microbial enzymes can offer novel biocatalyst with extraordinary properties.