PURPOSE: To produce a sheetlike sea tangle food having taste and sense of eating beyond conventional concepts of sea tangle, by finely cutting raw algae of sea tangle, seasoning the raw algae and treating the seasoned raw algae in the extruder.

CONSTITUTION: Raw algae are finely cut to about 1W2cm size and boiled down with a seasoning solution at about 60W95°C for about 5W6hr. Small pieces of the seasoned raw algae are milled or preferably simultaneously passed through a mincer, formed into a raw noodle form and then extruded through an extruder. The resultant pasty extrudate is subsequently extended into a sheetlike form in a rolling and the obtained sheet, if necessary, is then cut to a suitable size and then dried to provide about 2W3% moisture content.