Macroalgae species are fast growing and their polysaccharides are already used as food ingredient due to their properties as hydrocolloids or they have potential high value bioactivity. The degradation of these valuable polysaccharides to access the sugar components has remained mostly unexplored so far. One reason is the high structural complexity of algal polysaccharides, but also the need for suitable enzyme cocktails to obtain oligo‐ and monosaccharides. Among them, there are several rare sugars with high value. Recently, considerable progress was made in the discovery of highly specific carbohydrate‐active enzymes able to decompose complex marine carbohydrates such as carrageenan, laminarin, agar, porphyran and ulvan. This minireview summarizes these achievements and highlights potential applications of the now accessible abundant renewable resource of marine polysaccharides. Algae biomass is a source for many valuable compounds for the pharmaceutical and chemical industry. Especially marine polysaccharides contain rare sugars of interest, but a major bottleneck is access to these sugars. In this mini‐review the common knowledge of marine CAZyme‐based deconstruction of these polysaccharides and the biotechnological potential of the thus accessible oligo‐ and monosugars are described.