The present paper deals with the study of Chlorophyceae and analysis of water quality in Upper lake, Bhopal. Samples were collected from two sampling stations for a period of one year on monthly intervals from the lake. Physico-chemical parameters: temperature, pH, dissolved oxygen, alkalinity, water transparency and nutrients were measured simultaneously. Present investigation shows that the status of the Upper lake is eutrophic in nature. The physico-chemical parameters played an important role in distribution and diversity of algae. Higher peak of Chlorophycean algae were reported during summer. In Upper lake during the study period 60 genera of Chlorophyceae were identified. The Scendesmus was found the dominant species of this group. Second dominant species was Ankistrodesmus. The presence of Scenedesmus species indicated the organic pollution of lake water.