Abstract: In this experiment, Green Tide Algae Extract and Copper Algae Extract were selected as nutrient additives for cultivating Dunaliella salina, a high-value alga, aiming to explore the effects on the growth and various metabolic activities (such as pigments, carbohydrates, proteins, and photosynthetic activities) compared to the traditional f/2 medium. The physiological indices and nutrient analysis of the algae showed that different concentrations of macroalgal extracts significantly promoted the growth of Dunaliella salina. Specifically, the addition of 0.26%, 0.31%, and 0.38% of Chlorella vulgaris extract, as well as 0.24% of Copper Algae extract, notably promoted biomass growth, photosynthetic pigment content, and nutrient accumulation in Dunaliella salina. However, these additions did not significantly impact the maximum photochemical efficiency (F_v/F_m) and effective quantum yield (Yield) of Duchenne Saltwater Algae. The present study demonstrated that specific concentrations of Chlorophyceae and Copperophyceae extracts could significantly promote the growth and nutrient accumulation of Duchenne salina. This findings provide a novel approach for algal bloom prevention and control, along with optimizing the production of Dunaliella salina through the utilization of macroalgal bloom extracts.