This paper describes the planktonic diatom flora of the Sultan Sazligi marshes, Kayseri. Samples were collected systematically from the marshes over a period of years from three stations. The diatom flora of Sultan Sazligi is rich in terms of species and varieties, which are similar to those from many parts of Turkey. | Planktonic diatom (bacillariophyceae) flora of Sultan Sazligi marshes (Kayseri