AbstractBioindicators have become increasingly popular and have contributed significant amounts of useful information to the process of managing water resources. The ability of a species (or species assemblage) to adapt to a certain range of chemical, physical, and biological conditions is one criterion that can be used to assess the quality of its surrounding environment. Planktons that react quickly to changes in their environment have proven to be particularly valuable, and the identification of certain indicator species has become increasingly common in the process of determining the quality of the water. The “health” of an aquatic system can be inferred from the presence or absence of plankton, which act as early warning signals. When compared with the expense of assessing harmful contaminants, the overall cost of conducting routine monitoring of biological communities is far lower and has a higher degree of reliability. The ability of bioindicators to identify indirect biotic effects of pollutants, which is something that many physical or chemical tests are unable to do, is another advantage of using bioindicators. Different aquatic species as bioindicators tolerate different environmental conditions, and their different tolerances to particular environments help in identifying a particular environmental condition. Phytoplankton species like Euglena viridis, Oscillatoria limosa, Nitzschia palea, and Scenedesmus quadricauda, and zooplankton species like Branchionus sp., Molina sp., Keratella cochlearis, Daphnia sp., and Cyclopus sp. indicate water pollution. This review's objective is to highlight some recent research on planktons, focusing on their capabilities and opportunities for application as bioindicators of water quality.