Spirulina sp. is a photosynthetic blue-green microalga with high-quality bioactive compounds including pigments. This study was designed to investigate various phosphorus sources, such as Na2HPO4 and KH2PO4, addressing their impact on the biomass and pigments of Spirulina platensis using different concentrations. The highest biomass obtained was 2.75 and 1.98g at the concentration of 0.5g/ l for each source, respectively, which is lower compared to the control obtained from Zarrouk Medium. While, the results of chlorophyll a, total chlorophyll, and carotenoids were 25.47, 38.14, and 12.04, respectively, with 0.5g/ l KH2PO4 compared with the other source, Na2HPO4. Notably, the pigments tested in Zarrouk medium were the best compared to the other sources of phosphorus. It was concluded that carotenoids were not significantly affected by the change in phosphorus concentration. Interestingly, in this respect, it appeared that increasing the production of chlorophyll a resulted in an enhancement in biomass and total chlorophyll production in Spirulina. Chl a and total Chl concentrations were significantly different (P< 0.05).