An investigation was carried out to study the qualitative and quantitative status of the phytoplankton community of commercial tilapia-carp polyculture ponds in the Muhuri project area of Mirsharai, Chittagong. A total of 40 phytoplankton genera under 10 classes were identified. Chlorophyceae was noticed to be the most abundant (22.5%) class followed by Zygnematophyceae (17.5%), Trebouxiophyceae (15%), Bacillariophyceae (12.5%), Cyanophyceae (12.5%), Euglenoidea (10%), Ulvophyceae (2.5%), Crysophyceae (2.5%), Dinophyceae (2.5%) and Tentaculata (2.5%). The class Bacillarophyceae among 10 classes and the genera Cyclotella among all the 40 genera were found in highest concentration in the present investigation.