The objective of this study was to analyze the water quality parameter and the composition of phytoplankton communities related to the dynamics of fish farm irrigated with different water sources; Water and phytoplankton samples were collected from three different fish farms. Each farm was stocked with Nile tilapia in monoculture system. The obtained results indicated that, the values of studied parameters differed significantly (P <0.05) among three different water farm except water temperature. The highest values for Do and pH recorded in agriculture water farm, while TDS recorded the highest value in sewage water farm. Whereas the WQI demonstrated that it was between medium in sewage water farm and excellent in fresh and agricultural fish farms. Concerning phytoplankton community composition; Cyanophyceae dominated other groups in fresh water farm, while Chlorophyceae species were found in high densities at agriculture water farm and Bacillariophyceae dominated other group in sewage water farm. . The biodiversity index of overall phytoplankton genera was high in agricultural water farm. It's concluded that the water sources in the fish ponds had an influence on the plankton community, leading to an appearance of some species in related to organic polluted water. And the index based on WQI is currently more suitable than the phytoplankton species index for assessing the quality of the water of fish farms.