The study describes cultivation of Dunaliella salina at the saline cathode in a Photosynthetic Microbial Fuel Cell (PMFC). The alga was isolated from Salt Lake Sambhar, Rajasthan, India, and identified using 18S rDNA sequencing analysis. The alga growth in PMFC was tested at 0.5 M to 1.5 M sodium chloride. The highest power and current density were obtained at 0.5 M NaCl with the values of 213.38 mW m−2 and 1020.5 mA m−2, respectively. The specific growth rate of algae was 0.4 day−1 with 566 mg/L lipids and 348.9 ± 25.6 μg/mL of glycerol content at 0.5 M PMFC. The PMFC operating at 1.0 M NaCl led to high β-carotene production (24.42 ± 1.8 μg/100 mg). The salinity in natural water resources makes it difficult to apply them in bioprocesses. This study establishes the utility of D. salina in saline water-based PMFC for the generation of power and high-value Dunaliella biomass.