Abstract: The current study focused to evaluate one of the important trace metal concentrations in mixed zooplankton from the waters of Bay of Bengal and Andaman Sea. The average concentration of copper from northern Bay of Bengal, central Bay of Bengal, southern Bay of Bengal, and eastern Bay of Bengal on dry weight basis was reported as 65.36 mg.g-1, 58.54 mg.g-1, 48.86 mg.g-1, 43.50 mg.g-1 respectively and average surface sea water copper concentration from the northern Bay of Bengal, central Bay of Bengal, southern Bay of Bengal, and eastern Bay of Bengal was reported as 1.33 ppb, 1.30 ppb, 1.02 ppb, and 0.84 ppb respectively. The copper concentration in the mixed zooplankton from the waters of the Andaman Sea ranged from 36.25 to 58.32 mg.g-1 with an average of 43.14 mg.g-1 and its surface seawater concentrations ranged from 0.78 to 1.29 ppb with an average of 0.93 ppb.