The soluble and insoluble dietary fibre contents of seven marine algae ('sea vegetables'): wakame (Undaria pinnatifida), hijiki (Hijiki fusiformis), sea spaghetti (Himanthalia elongata), arame (Eisenia bicyclis), sea lettuce (Ulva lactuca), A O nori (Enteromorpha spp), and nori (Porphyra tenera) were determined by the gravimetric method of Prosky et al (J Assoc Anal Chem 1988, 71 1017-1023) following some adaptations. These seaweeds are particularly rich in dietary fibres with total dietary fibre contents varying between 32.7 and 74.6% (on a dry weight basis) of which 51.6 to 85.0% are water soluble. Marine algae appear to be good sources of fibres presenting great chemical, physico-chemical and rheological diversities that may be beneficial in nutrition.