A macroalga (Cladophora fracta) and a microalga (Chlorella protothecoides) samples were used in this work. Most current research on oil extraction is focused on microalgae to produce biodiesel from algal oil. The biodiesel from algal oil in itself is not significantly different from biodiesel produced from vegetable oils. Algal oils, as well as vegetable oils, are all highly viscous, with viscosities ranging 10-20 times those of no. 2 diesel fuel. Transesterification of the oil to its corresponding fatty ester is the most promising solution to the high viscosity problem. Fatty acid (m)ethyl esters produced from natural oils and fats is called biodiesel. Generally, methanol has been mostly used to produce biodiesel as it is the least expensive alcohol. The oil proportion from the lipid fractions of Chlorella protothecoides is considerable higher than that of Cladophora fracta. The higher heating value of Chlorella protothecoides (25.1 MJ/kg) also is higher than that of Cladophora fracta (21.1 MJ/kg). The average polyunsaturated fatty acids of Chlorella protothecoides (62.8%) also are higher than those of Cladophora fracta (50.9%).