Most of the phycological studies in the Philippines mainly focused on seasonal variations of phytoplankton in different lentic and lotic systems, with a little concern on epiphytic algal and cyanobacterial communities associated to aquatic macrophytes. In this study, the species composition and distribution of epiphytic algae living on the submerged plant tissues of aquatic macrophyte Hydrilla verticillata (L.f) Royle found at the largest freshwater shallow lake “Laguna de Bay" in the Philippines was studied, and documented with a detailed description for each species. A total of 15 algal species belonging to 12 genera of three algal phyla were observed including, 7 Cyanophyceae, 3 Bacillariophyceae 3 Trebouxiophyceae, and 2 Chlorophyceae. Of these taxa, the occurrence of a rare microalga Franceia amphitricha (Lagerheim) Hegewald is reported for the first time in the Philippines. These taxonomic records will add to the pool of data useful for understanding the epiphytic algal flora composition of aquatic macrophytes found in Philippine freshwater bodies.