Chlorella vulgaris, which could serve as a potential source of food and energy because of its photosynthetic efficiency, is a genus of single-celled green algae, belonging to the phylum Chlorophyta.In our study, a pathogenic organism targeting C.vulgaris was discovered.18S rRNA gene sequence analysis revealed that it shared 99.0% homology with Pseudobodo tremulans.Scanning electron microscope analysis showed that Pseudobodo sp cells were approximately 4-5 microns long, biflagellate with an anterior collar around the anterior part of the cell in unstressed feeding cells.