Dunaliella salina has been widely reported in the halophilic environment. The present study first time reveals and reports the presence of green alga D. salina identified by both morphological and molecular identification from Andaman and Nicobar Islands, a rainy tropical environment. Besides, it was adapted for the optimization of total carotenoid production by using Taguchi tool with various combinations of different parameters, like light intensity, pH, salinity, NaNO₃ and NaH₂PO₄ in basal De Walne’s medium of which 40µEm^-2s^-1 light intensity showed maximum production of 249.24 µg/mL of total carotenoid followed by NaNO₃, NaH₂PO₄, pH, and salinity. Hence, this study proves that D. salina possesses the character of adapting to the extreme habitats with total carotenoid production.