Marine enzyme biotechnology can offer novel biocatalysts with properties like high salt tolerance, hyperthermostability, barophilicity, cold adaptivity, and ease in large-scale cultivation. This review deals with the research and development work done on the occurrence, molecular biology, and bioprocessing of marine enzymes during the last decade. Exotic locations have been accessed for the search of novel enzymes. Scientists have isolated proteases and carbohydrases from deep sea hydrothermal vents. Cold active metabolic enzymes from psychrophilic marine microorganisms have received considerable research attention. Marine symbiont microorganisms growing in association with animals and plants were shown to produce enzymes of commercial interest. Microorganisms isolated from sediment and seawater have been the most widely studied, proteases, carbohydrases, and peroxidases being noteworthy. Enzymes from marine animals and plants were primarily studied for their metabolic roles, though proteases and peroxidases have found industrial applications. Novel techniques in molecular biology applied to assess the diversity of chitinases, nitrate, nitrite, ammonia-metabolizing, and pollutant-degrading enzymes are discussed. Genes encoding chitinases, proteases, and carbohydrases from microbial and animal sources have been cloned and characterized. Research on the bioprocessing of marine-derived enzymes, however, has been scanty, focusing mainly on the application of solid-state fermentation to the production of enzymes from microbial sources.