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This study investigated the impact of different nitrogen (sodium nitrate, urea, ammonium chloride, and ammonium nitrate) and carbon (sodium bicarbonate, sodium carbonate, and glucose) sources on the growth characteristics, biomass production, pigments, and polysaccharide content of the halophilic cyanobacterium Cyanothece sp. Growth trends were determined by cell density counting, and biomass was assessed by dry weight measurement. Pigment extraction and quantification were performed using spectrophotometry. Polysaccharide extraction was conducted using a hot water bath method at 80 °C. Based on the results, different nitrogen and carbon sources had no significant effect on the growth trend and biomass production of Cyanothece sp. However, the pigment profile and polysaccharide content of Cyanothece sp. biomass were significantly influenced by the different nitrogen and carbon sources in the culture medium. Among the tested treatments, the highest content of chlorophyll a and phycocyanin was obtained in the presence of sodium nitrate and potassium bicarbonate. The highest production of carotenoids and beta-carotene was observed in culture media containing urea or ammonium nitrate along with potassium carbonate. Comparison of the polysaccharide content in Cyanothece sp. biomass among different treatments showed that the culture medium containing sodium nitrate and potassium bicarbonate significantly increased biomass polysaccharide synthesis. Based on the results of this study, for producing Cyanothece sp. biomass rich in phycocyanin pigment with high polysaccharide content, it is recommended to use sodium nitrate and potassium bicarbonate as nitrogen and carbon sources, respectively.