Nowadays, biodiesel is considered as a useful fuel in the world due to its environmental advantages and renewable potential. In this regard, microalgae (cyanobacteria) have been introduced as appropriate sources of biodiesel production because of their lipid compounds. The purpose of this study was to investigate the potential of a cyanobacterium species, Spirulina major, as a major producer of biodiesel raw materials. In this study, after the purification phase, the samples were kept in Zarrouk culture medium at 30◦C, in constant light and pH=7. Then they were treated with different amounts of nitrogen (NaNo
3=0.25-1.5 g.L
-1) and pH (5-8). The results showed that the growth rate and production of various compounds by
S.Major were related to the amounts of the two environmental factors used in this study. Low nitrogen concentration (0.25 g.L
-1) and pH=7.5 are considered as the best conditions for increasing the growth rate, photosynthesis, production of fatty acids and other physiological parameters such as phycobiliproteins and chlorophyll except for the carotenoids that require higher nitrogen concentrations (1.5g.L
-1). In addition, the analysis of lipids showed that 80% of the fatty acids were saturated and unsaturated with single double bond. Palmitic acid and oleic acid were also the most important isolated fatty acids. Therefore,
S. Major can be introduced as a suitable candidate for biodiesel due to the production of the highest and the best lipid content.