The demand on fossil fuel is increasing due to the increases of population growth rates and higher fuel prices. Therefore, finding alternative clean and renewable source of energy is one of the most substantial needs nowadays Biodiesel is one of the potential renewable resources of energy which produces low emission gases, is sustainable, and can be produced using existing available technologies. The new resource of fuel has to be convincing, microalgae is one of the most promising sources of biodiesel and an economical substance due to its low coast and the availability. Microalgae has the highest of oil productivity and can produce many times more than crops The characteristics of microalgae’s biodiesel are very similar to diesel’s and it can be blended with diesel in any ratio. High oil prices, competing demands between foods and other biofuel sources and the world food crisis have ignited interest in farming algae for making biofuels. Using land that is not suitable for agriculture, using ocean and wastewater for producing and fast growth are algal fuels' attractive. About half weight of algae is oil that this lipid oil can be used to make biodiesel and this oil is capable of yielding 30 times more oil than the crops currently used in biofuel production.