Seaweeds from the genus Porphyra play a big economic role in seaweed aquaculture, mainly in Asia. In Europe, resources are put towards seaweed cultivation, but without attention to the Porphyra species which is also native to Europe. Different nomenclature and specifications are used to describe Porphyra, due to taxonomical reclassification and difficult phenotypical identification. Abiotic & biotic together with seasonal factors make for major variance in chemical compositions that are reported. This is also fueled by differences in chemical analytical methods and procedures followed. Combining taxonomical challenges, variance due to seasonal factors and differences in analysis, overviewing published research on Porphyra constituents such as protein, polysaccharides and fatty acids is warranted. Within this review, cellular consitutents found in Porphyra are discussed, including proteins, polysaccharides, fatty acids and mycosporine-like amino acids (MAA's). MAA's are considered amongst the strongest UV-photoprotectants found in nature and feature possible applications in cosmetics. As global interest in seaweeds as food, feed and industrial resource is emerging, opportunities for Porphyra constituents is rising.