In this work some major marine green algal taxa and the fresh water Chara species were selected and subjected to sterols and fatty acid analyses. Fatty acid analyses indicated that most of the extracted acid fractions were of the polyunsaturated ones (C16, C18 and C20) with some unusual fractions of C17 and C19. Fatty acids as a taxonomic tool gave a particular picture for each investigated taxa that characterized each member. High similarity matrices were observed between Dunaliella salina, Chlorella salina and Enteromorpha compressa. Sterol data indicated that most of the tested algae contained Δ⁵, Δ^5,22, Δ⁷sterols, peptosterol and the saturated nucleus campestanol. Sterol analyses showed clear variations between genera of the different orders: spinasterol was detected only in Ulvales while 5 β cholestanol and 5 β cholest-7-en- β -ol in Chlorococcales and 5, 22, 24 cholestatrien -3 β -ol was detected only in Charales. In general view, data of sterols and fatty acids indicated that Chara species could be placed among green algae.