The present study aims to compare the toxicity effect of Copper and Irgarol 1051 as antifouling agents on metabolites products in marine algae Dunaliella salina. Different concentrations of Cu (5, 15 & 25 mg/l) and Irgarol 1051 (0.012, 0.025 & 0.050 μg/l) were laboratories prepared and their impacts on growth, protein, and carbohydrates in Dunaliella salina were tested. Selections of these concentrations were initiated based on the response of the studied alga which had slightly or marked effects on its growth, and also to avoid the non-effective and directly lethal concentrations on the experimented alga. The obtained results showed stimulation in the growth of algae under the effect of the lowest concentration of the two tested antifoulings, however, there was a suppression of algal growth by increasing the concentration of the two antifoulings but with different degrees. There was a clear inhibition of protein and carbohydrate production by increasing the concentration of the two tested antifoulings. Also, Irgarol 1051 showed a toxic effect higher than Copper which is one of the essential micronutrients in the marine ecosystem.